72021889 has 2 divisors, whose sum is σ = 72021890. Its totient is φ = 72021888.

The previous prime is 72021857. The next prime is 72021967. The reversal of 72021889 is 98812027.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 45158400 + 26863489 = 6720^2 + 5183^2 .

It is a cyclic number.

It is not a de Polignac number, because 72021889 - 2⁵ = 72021857 is a prime.

It is equal to p_4229875 and since 72021889 and 4229875 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (72621889) 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, 36010944 + 36010945.

It is an arithmetic number, because the mean of its divisors is an integer number (36010945).

Almost surely, 2^72021889 is an apocalyptic number.

It is an amenable number.

72021889 is a deficient number, since it is larger than the sum of its proper divisors (1).

72021889 is an equidigital number, since it uses as much as digits as its factorization.

72021889 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16128, while the sum is 37.

The square root of 72021889 is about 8486.5710979170. The cubic root of 72021889 is about 416.0589186304.

The spelling of 72021889 in words is "seventy-two million, twenty-one thousand, eight hundred eighty-nine".