72309259521 has 8 divisors (see below), whose sum is σ = 107124828960. Its totient is φ = 48206172996.

The previous prime is 72309259511. The next prime is 72309259523. The reversal of 72309259521 is 12595290327.

72309259521 is a `hidden beast` number, since 7 + 2 + 30 + 9 + 2 + 595 + 21 = 666.

It is not a de Polignac number, because 72309259521 - 2¹¹ = 72309257473 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (72309259523) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1339060335 + ... + 1339060388.

It is an arithmetic number, because the mean of its divisors is an integer number (13390603620).

Almost surely, 2^72309259521 is an apocalyptic number.

It is an amenable number.

72309259521 is a deficient number, since it is larger than the sum of its proper divisors (34815569439).

72309259521 is a wasteful number, since it uses less digits than its factorization.

72309259521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2678120732 (or 2678120726 counting only the distinct ones).

The product of its (nonzero) digits is 340200, while the sum is 45.

The spelling of 72309259521 in words is "seventy-two billion, three hundred nine million, two hundred fifty-nine thousand, five hundred twenty-one".