631457857 has 2 divisors, whose sum is σ = 631457858. Its totient is φ = 631457856.

The previous prime is 631457839. The next prime is 631457903. The reversal of 631457857 is 758754136.

It is an a-pointer prime, because the next prime (631457903) can be obtained adding 631457857 to its sum of digits (46).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 521711281 + 109746576 = 22841^2 + 10476^2 .

It is a cyclic number.

It is not a de Polignac number, because 631457857 - 2¹¹ = 631455809 is a prime.

It is not a weakly prime, because it can be changed into another prime (631457257) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 315728928 + 315728929.

It is an arithmetic number, because the mean of its divisors is an integer number (315728929).

Almost surely, 2^631457857 is an apocalyptic number.

It is an amenable number.

631457857 is a deficient number, since it is larger than the sum of its proper divisors (1).

631457857 is an equidigital number, since it uses as much as digits as its factorization.

631457857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 705600, while the sum is 46.

The square root of 631457857 is about 25128.8252212474. The cubic root of 631457857 is about 857.9226302800.

The spelling of 631457857 in words is "six hundred thirty-one million, four hundred fifty-seven thousand, eight hundred fifty-seven".