521578979 has 2 divisors, whose sum is σ = 521578980. Its totient is φ = 521578978.

The previous prime is 521578957. The next prime is 521579011. The reversal of 521578979 is 979875125.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 521578979 - 2²⁴ = 504801763 is a prime.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 521578979.

It is not a weakly prime, because it can be changed into another prime (521578879) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260789489 + 260789490.

It is an arithmetic number, because the mean of its divisors is an integer number (260789490).

Almost surely, 2^521578979 is an apocalyptic number.

521578979 is a deficient number, since it is larger than the sum of its proper divisors (1).

521578979 is an equidigital number, since it uses as much as digits as its factorization.

521578979 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1587600, while the sum is 53.

The square root of 521578979 is about 22838.1036647091. The cubic root of 521578979 is about 804.9582576763.

The spelling of 521578979 in words is "five hundred twenty-one million, five hundred seventy-eight thousand, nine hundred seventy-nine".