72665523657321 has 16 divisors (see below), whose sum is σ = 110749464198528. Its totient is φ = 41515263676800.

The previous prime is 72665523657289. The next prime is 72665523657379. The reversal of 72665523657321 is 12375632556627.

It is not a de Polignac number, because 72665523657321 - 2⁵ = 72665523657289 is a prime.

It is not an unprimeable number, because it can be changed into a prime (72665523677321) 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, 328749340 + ... + 328970301.

It is an arithmetic number, because the mean of its divisors is an integer number (6921841512408).

Almost surely, 2^{72665523657321} is an apocalyptic number.

It is an amenable number.

72665523657321 is a deficient number, since it is larger than the sum of its proper divisors (38083940541207).

72665523657321 is a wasteful number, since it uses less digits than its factorization.

72665523657321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 657724912.

The product of its digits is 95256000, while the sum is 60.

The spelling of 72665523657321 in words is "seventy-two trillion, six hundred sixty-five billion, five hundred twenty-three million, six hundred fifty-seven thousand, three hundred twenty-one".