631931 has 2 divisors, whose sum is σ = 631932. Its totient is φ = 631930.

The previous prime is 631927. The next prime is 631937. The reversal of 631931 is 139136.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 631931 - 2² = 631927 is a prime.

It is a super-2 number, since 2×631931² = 798673577522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 631897 and 631906.

It is not a weakly prime, because it can be changed into another prime (631937) 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, 315965 + 315966.

It is an arithmetic number, because the mean of its divisors is an integer number (315966).

2⁶³¹⁹³¹ is an apocalyptic number.

631931 is a deficient number, since it is larger than the sum of its proper divisors (1).

631931 is an equidigital number, since it uses as much as digits as its factorization.

631931 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 486, while the sum is 23.

The square root of 631931 is about 794.9408783048. The cubic root of 631931 is about 85.8136853468.

The spelling of 631931 in words is "six hundred thirty-one thousand, nine hundred thirty-one".