72351509368321 has 6 divisors (see below), whose sum is σ = 76857831751430. Its totient is φ = 68095538228736.

The previous prime is 72351509368249. The next prime is 72351509368337. The reversal of 72351509368321 is 12386390515327.

It can be written as a sum of positive squares in 3 ways, for example, as 30594892500225 + 41756616868096 = 5531265^2 + 6461936^2 .

It is not a de Polignac number, because 72351509368321 - 2²³ = 72351500979713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72351509368351) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 125175621456 + ... + 125175622033.

Almost surely, 2^{72351509368321} is an apocalyptic number.

It is an amenable number.

72351509368321 is a deficient number, since it is larger than the sum of its proper divisors (4506322383109).

72351509368321 is a wasteful number, since it uses less digits than its factorization.

72351509368321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250351243523 (or 250351243506 counting only the distinct ones).

The product of its (nonzero) digits is 8164800, while the sum is 55.

The spelling of 72351509368321 in words is "seventy-two trillion, three hundred fifty-one billion, five hundred nine million, three hundred sixty-eight thousand, three hundred twenty-one".