521539990 has 16 divisors (see below), whose sum is σ = 940740480. Its totient is φ = 208178560.

The previous prime is 521539961. The next prime is 521540003. The reversal of 521539990 is 99935125.

It is a super-2 number, since 2×521539990² = 544007922338400200, which contains 22 as substring.

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, 49651 + ... + 59230.

It is an arithmetic number, because the mean of its divisors is an integer number (58796280).

Almost surely, 2^521539990 is an apocalyptic number.

521539990 is a deficient number, since it is larger than the sum of its proper divisors (419200490).

521539990 is a wasteful number, since it uses less digits than its factorization.

521539990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109367.

The product of its (nonzero) digits is 109350, while the sum is 43.

The square root of 521539990 is about 22837.2500533668. The cubic root of 521539990 is about 804.9381998003.

The spelling of 521539990 in words is "five hundred twenty-one million, five hundred thirty-nine thousand, nine hundred ninety".