521978964 has 24 divisors (see below), whose sum is σ = 1311639840. Its totient is φ = 160608864.

The previous prime is 521978929. The next prime is 521978983. The reversal of 521978964 is 469879125.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1672854 + ... + 1673165.

It is an arithmetic number, because the mean of its divisors is an integer number (54651660).

Almost surely, 2^521978964 is an apocalyptic number.

It is an amenable number.

521978964 is an abundant number, since it is smaller than the sum of its proper divisors (789660876).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

521978964 is a wasteful number, since it uses less digits than its factorization.

521978964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3346039 (or 3346037 counting only the distinct ones).

The product of its digits is 1088640, while the sum is 51.

The square root of 521978964 is about 22846.8589526000. The cubic root of 521978964 is about 805.1639721018.

The spelling of 521978964 in words is "five hundred twenty-one million, nine hundred seventy-eight thousand, nine hundred sixty-four".