2691631 has 2 divisors, whose sum is σ = 2691632. Its totient is φ = 2691630.

The previous prime is 2691617. The next prime is 2691641. The reversal of 2691631 is 1361962.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2691631 - 2⁵ = 2691599 is a prime.

It is a super-2 number, since 2×2691631² = 14489754880322, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 2691631.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2691641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1345815 + 1345816.

It is an arithmetic number, because the mean of its divisors is an integer number (1345816).

2^2691631 is an apocalyptic number.

2691631 is a deficient number, since it is larger than the sum of its proper divisors (1).

2691631 is an equidigital number, since it uses as much as digits as its factorization.

2691631 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1944, while the sum is 28.

The square root of 2691631 is about 1640.6190904655. The cubic root of 2691631 is about 139.1036440391.

The spelling of 2691631 in words is "two million, six hundred ninety-one thousand, six hundred thirty-one".