31864393 has 4 divisors (see below), whose sum is σ = 34761168. Its totient is φ = 28967620.

The previous prime is 31864379. The next prime is 31864397. The reversal of 31864393 is 39346813.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a de Polignac number, because none of the positive numbers 2^k-31864393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31864397) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1448371 + ... + 1448392.

It is an arithmetic number, because the mean of its divisors is an integer number (8690292).

Almost surely, 2^31864393 is an apocalyptic number.

It is an amenable number.

31864393 is a deficient number, since it is larger than the sum of its proper divisors (2896775).

31864393 is a wasteful number, since it uses less digits than its factorization.

31864393 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2896774.

The product of its digits is 46656, while the sum is 37.

The square root of 31864393 is about 5644.8554454477. The cubic root of 31864393 is about 317.0311114632.

The spelling of 31864393 in words is "thirty-one million, eight hundred sixty-four thousand, three hundred ninety-three".