31120631 has 2 divisors, whose sum is σ = 31120632. Its totient is φ = 31120630.

The previous prime is 31120619. The next prime is 31120657. The reversal of 31120631 is 13602113.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31120631 is a prime.

It is a super-2 number, since 2×31120631² = 1936987347676322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31120031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15560315 + 15560316.

It is an arithmetic number, because the mean of its divisors is an integer number (15560316).

Almost surely, 2^31120631 is an apocalyptic number.

31120631 is a deficient number, since it is larger than the sum of its proper divisors (1).

31120631 is an equidigital number, since it uses as much as digits as its factorization.

31120631 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108, while the sum is 17.

The square root of 31120631 is about 5578.5868282209. The cubic root of 31120631 is about 314.5450086942.

Adding to 31120631 its reverse (13602113), we get a palindrome (44722744).

The spelling of 31120631 in words is "thirty-one million, one hundred twenty thousand, six hundred thirty-one".