Srinivasa Ramanujan: Life, Mathematics and Legacy

Srinivasa Ramanujan (1887–1920) was an Indian mathematician who, with almost no formal training, produced thousands of results in number theory, infinite series and continued fractions. After writing to G. H. Hardy in 1913 he worked at Cambridge, and in 1918 he became a Fellow of the Royal Society. He died in Kumbakonam at 32. India marks his birthday, 22 December, as National Mathematics Day.

Early life

Ramanujan was born in Erode and grew up in Kumbakonam, where his father worked as a clerk in a sari shop. As a schoolboy he worked through a book of mathematical results by G. S. Carr and began recording his own discoveries in notebooks. His focus on mathematics cost him his college scholarships, and he left without a degree. In 1912 he became a clerk at the Madras Port Trust.

The letter to Hardy and Cambridge

In January 1913 Ramanujan wrote to G. H. Hardy at Cambridge, enclosing pages of theorems. Hardy recognised his originality and arranged for him to come to England. He sailed in 1914 and worked with Hardy and J. E. Littlewood at Trinity College. Their joint work included an asymptotic formula for the partition function, the number of ways of writing a number as a sum of positive integers.

In 1918 he was elected a Fellow of the Royal Society, one of the first Indians to receive the honour, and a Fellow of Trinity College.

Faith

Ramanujan was a devout Hindu and kept his religious practice in England, including a strict vegetarian diet. His biographer Robert Kanigel records that he credited insights to the family goddess Namagiri of Namakkal, and that his mother's dream of the goddess was part of the family's decision to let him travel to England.

Illness and death

Ramanujan fell ill in England in 1917. He returned to India in 1919 and died in Kumbakonam on 26 April 1920, aged 32. Doctors have since suggested that his illness may have been hepatic amoebiasis; the cause is not certain.

His legacy

Ramanujan left notebooks of results, many stated without proof. Mathematicians, notably Bruce Berndt, spent decades proving them. His "lost notebook", found in 1976 by George Andrews, contained his last work on mock theta functions. The number 1729, the "Hardy–Ramanujan number", recalls a story told by Hardy about a taxi number that Ramanujan described as the smallest number expressible as the sum of two cubes in two ways. In 2012 India declared 22 December National Mathematics Day.

Frequently asked questions

When was Srinivasa Ramanujan born?

On 22 December 1887 in Erode, Tamil Nadu.

Why is 22 December National Mathematics Day?

It is Ramanujan's birthday. India declared it National Mathematics Day in 2012, the 125th anniversary of his birth.

What is the Hardy–Ramanujan number?

1729, the smallest number that is the sum of two cubes in two different ways (1³ + 12³ and 9³ + 10³).

Was Ramanujan religious?

Yes. He was a devout Hindu who credited insights to the goddess Namagiri, according to his biographers.

Sources

• Robert Kanigel, The Man Who Knew Infinity: A Life of the Genius Ramanujan (Scribner, 1991).
• G. H. Hardy, Ramanujan: Twelve Lectures on Subjects Suggested by His Life and Work (Cambridge University Press, 1940).
• Press Information Bureau, National Mathematics Day releases.

Last reviewed: 12 November 2026.

Related: Aryabhata · Brahmagupta