64131510521 has 16 divisors (see below), whose sum is σ = 73449196800. Its totient is φ = 55504424448.

The previous prime is 64131510491. The next prime is 64131510587. The reversal of 64131510521 is 12501513146.

It is a cyclic number.

It is not a de Polignac number, because 64131510521 - 2¹⁴ = 64131494137 is a prime.

It is a super-2 number, since 2×64131510521² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (64131530521) 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, 1314401 + ... + 1362318.

It is an arithmetic number, because the mean of its divisors is an integer number (4590574800).

Almost surely, 2^64131510521 is an apocalyptic number.

It is an amenable number.

64131510521 is a deficient number, since it is larger than the sum of its proper divisors (9317686279).

64131510521 is a wasteful number, since it uses less digits than its factorization.

64131510521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2676848.

The product of its (nonzero) digits is 3600, while the sum is 29.

The spelling of 64131510521 in words is "sixty-four billion, one hundred thirty-one million, five hundred ten thousand, five hundred twenty-one".