813900961 has 2 divisors, whose sum is σ = 813900962. Its totient is φ = 813900960.

The previous prime is 813900937. The next prime is 813901051. The reversal of 813900961 is 169009318.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 690690961 + 123210000 = 26281^2 + 11100^2 .

It is a cyclic number.

It is not a de Polignac number, because 813900961 - 2¹⁵ = 813868193 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 813900961.

It is not a weakly prime, because it can be changed into another prime (813900911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 406950480 + 406950481.

It is an arithmetic number, because the mean of its divisors is an integer number (406950481).

Almost surely, 2^813900961 is an apocalyptic number.

It is an amenable number.

813900961 is a deficient number, since it is larger than the sum of its proper divisors (1).

813900961 is an equidigital number, since it uses as much as digits as its factorization.

813900961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11664, while the sum is 37.

The square root of 813900961 is about 28528.9495250000. The cubic root of 813900961 is about 933.6637994602.

The spelling of 813900961 in words is "eight hundred thirteen million, nine hundred thousand, nine hundred sixty-one".