520651665 has 64 divisors (see below), whose sum is σ = 976158720. Its totient is φ = 262906560.

The previous prime is 520651657. The next prime is 520651711. The reversal of 520651665 is 566156025.

It is a happy number.

520651665 is a `hidden beast` number, since 520 + 65 + 16 + 65 = 666.

It is not a de Polignac number, because 520651665 - 2³ = 520651657 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 195372 + ... + 198018.

It is an arithmetic number, because the mean of its divisors is an integer number (15252480).

Almost surely, 2^520651665 is an apocalyptic number.

It is an amenable number.

520651665 is a deficient number, since it is larger than the sum of its proper divisors (455507055).

520651665 is a wasteful number, since it uses less digits than its factorization.

520651665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2739 (or 2733 counting only the distinct ones).

The product of its (nonzero) digits is 54000, while the sum is 36.

The square root of 520651665 is about 22817.7927284827. The cubic root of 520651665 is about 804.4809302409.

The spelling of 520651665 in words is "five hundred twenty million, six hundred fifty-one thousand, six hundred sixty-five".