31640769 has 12 divisors (see below), whose sum is σ = 47279700. Its totient is φ = 20366304.

The previous prime is 31640767. The next prime is 31640773. The reversal of 31640769 is 96704613.

31640769 is a `hidden beast` number, since 3 + 1 + 640 + 7 + 6 + 9 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 16524225 + 15116544 = 4065^2 + 3888^2 .

It is not a de Polignac number, because 31640769 - 2¹ = 31640767 is a prime.

It is a super-2 number, since 2×31640769² = 2002276525822722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (31640767) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 60354 + ... + 60875.

It is an arithmetic number, because the mean of its divisors is an integer number (3939975).

Almost surely, 2^31640769 is an apocalyptic number.

It is an amenable number.

31640769 is a deficient number, since it is larger than the sum of its proper divisors (15638931).

31640769 is a wasteful number, since it uses less digits than its factorization.

31640769 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121264 (or 121261 counting only the distinct ones).

The product of its (nonzero) digits is 27216, while the sum is 36.

The square root of 31640769 is about 5625.0127999854. The cubic root of 31640769 is about 316.2877293069.

The spelling of 31640769 in words is "thirty-one million, six hundred forty thousand, seven hundred sixty-nine".