64764367521 has 16 divisors (see below), whose sum is σ = 99025390464. Its totient is φ = 36881898624.

The previous prime is 64764367513. The next prime is 64764367529. The reversal of 64764367521 is 12576346746.

It is an interprime number because it is at equal distance from previous prime (64764367513) and next prime (64764367529).

It is not a de Polignac number, because 64764367521 - 2³ = 64764367513 is a prime.

It is not an unprimeable number, because it can be changed into a prime (64764367529) 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, 5256676 + ... + 5268981.

It is an arithmetic number, because the mean of its divisors is an integer number (6189086904).

Almost surely, 2^64764367521 is an apocalyptic number.

It is an amenable number.

64764367521 is a deficient number, since it is larger than the sum of its proper divisors (34261022943).

64764367521 is a wasteful number, since it uses less digits than its factorization.

64764367521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10525960.

The product of its digits is 5080320, while the sum is 51.

The spelling of 64764367521 in words is "sixty-four billion, seven hundred sixty-four million, three hundred sixty-seven thousand, five hundred twenty-one".