31699681 has 8 divisors (see below), whose sum is σ = 35622720. Its totient is φ = 27988752.

The previous prime is 31699669. The next prime is 31699711. The reversal of 31699681 is 18699613.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 31699681 - 2⁵ = 31699649 is a prime.

It is a super-2 number, since 2×31699681² = 2009739551003522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31699651) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 52711 + ... + 53308.

It is an arithmetic number, because the mean of its divisors is an integer number (4452840).

Almost surely, 2^31699681 is an apocalyptic number.

It is an amenable number.

31699681 is a deficient number, since it is larger than the sum of its proper divisors (3923039).

31699681 is a wasteful number, since it uses less digits than its factorization.

31699681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106055.

The product of its digits is 69984, while the sum is 43.

The square root of 31699681 is about 5630.2469750447. The cubic root of 31699681 is about 316.4839064847.

The spelling of 31699681 in words is "thirty-one million, six hundred ninety-nine thousand, six hundred eighty-one".