521521264 has 20 divisors (see below), whose sum is σ = 1102306680. Its totient is φ = 237055040.

The previous prime is 521521261. The next prime is 521521267. The reversal of 521521264 is 462125125.

It is an interprime number because it is at equal distance from previous prime (521521261) and next prime (521521267).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (521521261) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1481419 + ... + 1481770.

It is an arithmetic number, because the mean of its divisors is an integer number (55115334).

Almost surely, 2^521521264 is an apocalyptic number.

It is an amenable number.

521521264 is an abundant number, since it is smaller than the sum of its proper divisors (580785416).

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

521521264 is a wasteful number, since it uses less digits than its factorization.

521521264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2963208 (or 2963202 counting only the distinct ones).

The product of its digits is 4800, while the sum is 28.

The square root of 521521264 is about 22836.8400616197. The cubic root of 521521264 is about 804.9285658614.

Adding to 521521264 its reverse (462125125), we get a palindrome (983646389).

The spelling of 521521264 in words is "five hundred twenty-one million, five hundred twenty-one thousand, two hundred sixty-four".