72385728921 has 16 divisors (see below), whose sum is σ = 116987037120. Its totient is φ = 43870138560.

The previous prime is 72385728911. The next prime is 72385728923. The reversal of 72385728921 is 12982758327.

It is not a de Polignac number, because 72385728921 - 2¹⁵ = 72385696153 is a prime.

It is a super-3 number, since 3×72385728921³ (a number of 34 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (72385728923) 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, 121861200 + ... + 121861793.

It is an arithmetic number, because the mean of its divisors is an integer number (7311689820).

Almost surely, 2^72385728921 is an apocalyptic number.

It is an amenable number.

72385728921 is a deficient number, since it is larger than the sum of its proper divisors (44601308199).

72385728921 is a wasteful number, since it uses less digits than its factorization.

72385728921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 243723013 (or 243723007 counting only the distinct ones).

The product of its digits is 3386880, while the sum is 54.

The spelling of 72385728921 in words is "seventy-two billion, three hundred eighty-five million, seven hundred twenty-eight thousand, nine hundred twenty-one".