521159985 has 24 divisors (see below), whose sum is σ = 927761640. Its totient is φ = 270438912.

The previous prime is 521159983. The next prime is 521159999. The reversal of 521159985 is 589951125.

521159985 is a `hidden beast` number, since 52 + 1 + 1 + 599 + 8 + 5 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 168584256 + 352575729 = 12984^2 + 18777^2 .

It is not a de Polignac number, because 521159985 - 2¹ = 521159983 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 521159985.

It is not an unprimeable number, because it can be changed into a prime (521159983) by changing a digit.

It is an upside-down number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 154840 + ... + 158169.

It is an arithmetic number, because the mean of its divisors is an integer number (38656735).

Almost surely, 2^521159985 is an apocalyptic number.

It is an amenable number.

521159985 is a deficient number, since it is larger than the sum of its proper divisors (406601655).

521159985 is a wasteful number, since it uses less digits than its factorization.

521159985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 313057 (or 313054 counting only the distinct ones).

The product of its digits is 162000, while the sum is 45.

The square root of 521159985 is about 22828.9286870847. The cubic root of 521159985 is about 804.7426540020.

The spelling of 521159985 in words is "five hundred twenty-one million, one hundred fifty-nine thousand, nine hundred eighty-five".