72456817 has 2 divisors, whose sum is σ = 72456818. Its totient is φ = 72456816.

The previous prime is 72456803. The next prime is 72456821. The reversal of 72456817 is 71865427.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 48944016 + 23512801 = 6996^2 + 4849^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72456817 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 72456817.

It is not a weakly prime, because it can be changed into another prime (72456847) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36228408 + 36228409.

It is an arithmetic number, because the mean of its divisors is an integer number (36228409).

Almost surely, 2^72456817 is an apocalyptic number.

It is an amenable number.

72456817 is a deficient number, since it is larger than the sum of its proper divisors (1).

72456817 is an equidigital number, since it uses as much as digits as its factorization.

72456817 is an evil number, because the sum of its binary digits is even.

The product of its digits is 94080, while the sum is 40.

The square root of 72456817 is about 8512.1570121797. The cubic root of 72456817 is about 416.8947415514.

The spelling of 72456817 in words is "seventy-two million, four hundred fifty-six thousand, eight hundred seventeen".