31897913 has 8 divisors (see below), whose sum is σ = 32773248. Its totient is φ = 31030864.

The previous prime is 31897889. The next prime is 31897919. The reversal of 31897913 is 31979813.

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 31897913 - 2¹⁰ = 31896889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31897919) 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, 6170 + ... + 10092.

It is an arithmetic number, because the mean of its divisors is an integer number (4096656).

Almost surely, 2^31897913 is an apocalyptic number.

It is an amenable number.

31897913 is a deficient number, since it is larger than the sum of its proper divisors (875335).

31897913 is a wasteful number, since it uses less digits than its factorization.

31897913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4143.

The product of its digits is 40824, while the sum is 41.

The square root of 31897913 is about 5647.8237401675. The cubic root of 31897913 is about 317.1422402989.

The spelling of 31897913 in words is "thirty-one million, eight hundred ninety-seven thousand, nine hundred thirteen".