72639967 has 2 divisors, whose sum is σ = 72639968. Its totient is φ = 72639966.

The previous prime is 72639961. The next prime is 72639971. The reversal of 72639967 is 76993627.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72639967 is a prime.

It is a super-2 number, since 2×72639967² = 10553129611522178, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 72639967.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72639961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36319983 + 36319984.

It is an arithmetic number, because the mean of its divisors is an integer number (36319984).

Almost surely, 2^72639967 is an apocalyptic number.

72639967 is a deficient number, since it is larger than the sum of its proper divisors (1).

72639967 is an equidigital number, since it uses as much as digits as its factorization.

72639967 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 857304, while the sum is 49.

The square root of 72639967 is about 8522.9083651064. The cubic root of 72639967 is about 417.2457093480.

The spelling of 72639967 in words is "seventy-two million, six hundred thirty-nine thousand, nine hundred sixty-seven".