391431956 has 12 divisors (see below), whose sum is σ = 695230368. Its totient is φ = 192794712.

The previous prime is 391431893. The next prime is 391431973. The reversal of 391431956 is 659134193.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 730016 + ... + 730551.

It is an arithmetic number, because the mean of its divisors is an integer number (57935864).

Almost surely, 2^391431956 is an apocalyptic number.

It is an amenable number.

391431956 is a deficient number, since it is larger than the sum of its proper divisors (303798412).

391431956 is a wasteful number, since it uses less digits than its factorization.

391431956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1460638 (or 1460636 counting only the distinct ones).

The product of its digits is 87480, while the sum is 41.

The square root of 391431956 is about 19784.6393952480. The cubic root of 391431956 is about 731.5074597747.

The spelling of 391431956 in words is "three hundred ninety-one million, four hundred thirty-one thousand, nine hundred fifty-six".