331564993 has 2 divisors, whose sum is σ = 331564994. Its totient is φ = 331564992.

The previous prime is 331564943. The next prime is 331565009. The reversal of 331564993 is 399465133.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 191213584 + 140351409 = 13828^2 + 11847^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-331564993 is a prime.

It is not a weakly prime, because it can be changed into another prime (331564903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 165782496 + 165782497.

It is an arithmetic number, because the mean of its divisors is an integer number (165782497).

Almost surely, 2^331564993 is an apocalyptic number.

It is an amenable number.

331564993 is a deficient number, since it is larger than the sum of its proper divisors (1).

331564993 is an equidigital number, since it uses as much as digits as its factorization.

331564993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 262440, while the sum is 43.

The square root of 331564993 is about 18208.9261901958. The cubic root of 331564993 is about 692.1330010711.

The spelling of 331564993 in words is "three hundred thirty-one million, five hundred sixty-four thousand, nine hundred ninety-three".