72389830021 has 2 divisors, whose sum is σ = 72389830022. Its totient is φ = 72389830020.

The previous prime is 72389830013. The next prime is 72389830031. The reversal of 72389830021 is 12003898327.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 71670785796 + 719044225 = 267714^2 + 26815^2 .

It is a cyclic number.

It is not a de Polignac number, because 72389830021 - 2³ = 72389830013 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 72389830021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72389830001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36194915010 + 36194915011.

It is an arithmetic number, because the mean of its divisors is an integer number (36194915011).

Almost surely, 2^72389830021 is an apocalyptic number.

It is an amenable number.

72389830021 is a deficient number, since it is larger than the sum of its proper divisors (1).

72389830021 is an equidigital number, since it uses as much as digits as its factorization.

72389830021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 145152, while the sum is 43.

The spelling of 72389830021 in words is "seventy-two billion, three hundred eighty-nine million, eight hundred thirty thousand, twenty-one".