631591057 has 4 divisors (see below), whose sum is σ = 632229376. Its totient is φ = 630952740.

The previous prime is 631591039. The next prime is 631591069. The reversal of 631591057 is 750195136.

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 cyclic number.

It is not a de Polignac number, because 631591057 - 2²³ = 623202449 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (631591007) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 317673 + ... + 319654.

It is an arithmetic number, because the mean of its divisors is an integer number (158057344).

Almost surely, 2^631591057 is an apocalyptic number.

It is an amenable number.

631591057 is a deficient number, since it is larger than the sum of its proper divisors (638319).

631591057 is an equidigital number, since it uses as much as digits as its factorization.

631591057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 638318.

The product of its (nonzero) digits is 28350, while the sum is 37.

The square root of 631591057 is about 25131.4754242563. The cubic root of 631591057 is about 857.9829495654.

The spelling of 631591057 in words is "six hundred thirty-one million, five hundred ninety-one thousand, fifty-seven".