72324756056521 has 2 divisors, whose sum is σ = 72324756056522. Its totient is φ = 72324756056520.

The previous prime is 72324756056507. The next prime is 72324756056549. The reversal of 72324756056521 is 12565065742327.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 64990603805625 + 7334152250896 = 8061675^2 + 2708164^2 .

It is a cyclic number.

It is not a de Polignac number, because 72324756056521 - 2³⁹ = 71775000242633 is a prime.

It is not a weakly prime, because it can be changed into another prime (72324756756521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36162378028260 + 36162378028261.

It is an arithmetic number, because the mean of its divisors is an integer number (36162378028261).

Almost surely, 2^{72324756056521} is an apocalyptic number.

It is an amenable number.

72324756056521 is a deficient number, since it is larger than the sum of its proper divisors (1).

72324756056521 is an equidigital number, since it uses as much as digits as its factorization.

72324756056521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 21168000, while the sum is 55.

The spelling of 72324756056521 in words is "seventy-two trillion, three hundred twenty-four billion, seven hundred fifty-six million, fifty-six thousand, five hundred twenty-one".