521387172 has 48 divisors (see below), whose sum is σ = 1398364800. Its totient is φ = 167801760.

The previous prime is 521387147. The next prime is 521387173. The reversal of 521387172 is 271783125.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (521387173) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 80104 + ... + 86367.

It is an arithmetic number, because the mean of its divisors is an integer number (29132600).

Almost surely, 2^521387172 is an apocalyptic number.

It is an amenable number.

521387172 is an abundant number, since it is smaller than the sum of its proper divisors (876977628).

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

521387172 is a wasteful number, since it uses less digits than its factorization.

521387172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166513 (or 166505 counting only the distinct ones).

The product of its digits is 23520, while the sum is 36.

The square root of 521387172 is about 22833.9040026010. The cubic root of 521387172 is about 804.8595729998.

The spelling of 521387172 in words is "five hundred twenty-one million, three hundred eighty-seven thousand, one hundred seventy-two".