520665564 has 24 divisors (see below), whose sum is σ = 1215343360. Its totient is φ = 173489904.

The previous prime is 520665547. The next prime is 520665581. The reversal of 520665564 is 465566025.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (520665547) and next prime (520665581).

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, 33627 + ... + 46605.

Almost surely, 2^520665564 is an apocalyptic number.

It is an amenable number.

520665564 is an abundant number, since it is smaller than the sum of its proper divisors (694677796).

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

520665564 is a wasteful number, since it uses less digits than its factorization.

520665564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16329 (or 16327 counting only the distinct ones).

The product of its (nonzero) digits is 216000, while the sum is 39.

The square root of 520665564 is about 22818.0972914045. The cubic root of 520665564 is about 804.4880888217.

It can be divided in two parts, 52066 and 5564, that added together give a triangular number (57630 = T₃₃₉).

The spelling of 520665564 in words is "five hundred twenty million, six hundred sixty-five thousand, five hundred sixty-four".