690679931 has 2 divisors, whose sum is σ = 690679932. Its totient is φ = 690679930.

The previous prime is 690679897. The next prime is 690679967. The reversal of 690679931 is 139976096.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-690679931 is a prime.

It is a super-2 number, since 2×690679931² = 954077534172329522, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 690679931.

It is not a weakly prime, because it can be changed into another prime (690679981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 345339965 + 345339966.

It is an arithmetic number, because the mean of its divisors is an integer number (345339966).

Almost surely, 2^690679931 is an apocalyptic number.

690679931 is a deficient number, since it is larger than the sum of its proper divisors (1).

690679931 is an equidigital number, since it uses as much as digits as its factorization.

690679931 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 551124, while the sum is 50.

The square root of 690679931 is about 26280.7901517439. The cubic root of 690679931 is about 883.9457504945.

The spelling of 690679931 in words is "six hundred ninety million, six hundred seventy-nine thousand, nine hundred thirty-one".