521979 has 4 divisors (see below), whose sum is σ = 695976. Its totient is φ = 347984.

The previous prime is 521929. The next prime is 521981. The reversal of 521979 is 979125.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 521979 - 2⁸ = 521723 is a prime.

It is a D-number.

It is not an unprimeable number, because it can be changed into a prime (521929) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 86994 + ... + 86999.

It is an arithmetic number, because the mean of its divisors is an integer number (173994).

2⁵²¹⁹⁷⁹ is an apocalyptic number.

521979 is a deficient number, since it is larger than the sum of its proper divisors (173997).

521979 is a wasteful number, since it uses less digits than its factorization.

521979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173996.

The product of its digits is 5670, while the sum is 33.

The square root of 521979 is about 722.4811416224. The cubic root of 521979 is about 80.5163990612.

The spelling of 521979 in words is "five hundred twenty-one thousand, nine hundred seventy-nine".