72021577 has 2 divisors, whose sum is σ = 72021578. Its totient is φ = 72021576.

The previous prime is 72021563. The next prime is 72021601. The reversal of 72021577 is 77512027.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 71419401 + 602176 = 8451^2 + 776^2 .

It is a cyclic number.

It is not a de Polignac number, because 72021577 - 2¹¹ = 72019529 is a prime.

It is not a weakly prime, because it can be changed into another prime (72021527) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36010788 + 36010789.

It is an arithmetic number, because the mean of its divisors is an integer number (36010789).

Almost surely, 2^72021577 is an apocalyptic number.

It is an amenable number.

72021577 is a deficient number, since it is larger than the sum of its proper divisors (1).

72021577 is an equidigital number, since it uses as much as digits as its factorization.

72021577 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6860, while the sum is 31.

The square root of 72021577 is about 8486.5527159147. The cubic root of 72021577 is about 416.0583178381.

The spelling of 72021577 in words is "seventy-two million, twenty-one thousand, five hundred seventy-seven".