31697081 has 8 divisors (see below), whose sum is σ = 34260744. Its totient is φ = 29151360.

The previous prime is 31697069. The next prime is 31697089. The reversal of 31697081 is 18079613.

It can be written as a sum of positive squares in 4 ways, for example, as 839056 + 30858025 = 916^2 + 5555^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31697081 is a prime.

It is a super-2 number, since 2×31697081² = 2009409887841122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31697089) 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, 686 + ... + 7991.

It is an arithmetic number, because the mean of its divisors is an integer number (4282593).

Almost surely, 2^31697081 is an apocalyptic number.

It is an amenable number.

31697081 is a deficient number, since it is larger than the sum of its proper divisors (2563663).

31697081 is a wasteful number, since it uses less digits than its factorization.

31697081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8971.

The product of its (nonzero) digits is 9072, while the sum is 35.

The square root of 31697081 is about 5630.0160745774. The cubic root of 31697081 is about 316.4752536042.

The spelling of 31697081 in words is "thirty-one million, six hundred ninety-seven thousand, eighty-one".