72807817 has 2 divisors, whose sum is σ = 72807818. Its totient is φ = 72807816.

The previous prime is 72807797. The next prime is 72807827. The reversal of 72807817 is 71870827.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 68211081 + 4596736 = 8259^2 + 2144^2 .

It is a cyclic number.

It is not a de Polignac number, because 72807817 - 2⁷ = 72807689 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 72807817.

It is not a weakly prime, because it can be changed into another prime (72807827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36403908 + 36403909.

It is an arithmetic number, because the mean of its divisors is an integer number (36403909).

Almost surely, 2^72807817 is an apocalyptic number.

It is an amenable number.

72807817 is a deficient number, since it is larger than the sum of its proper divisors (1).

72807817 is an equidigital number, since it uses as much as digits as its factorization.

72807817 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 43904, while the sum is 40.

The square root of 72807817 is about 8532.7496740500. The cubic root of 72807817 is about 417.5668402673.

The spelling of 72807817 in words is "seventy-two million, eight hundred seven thousand, eight hundred seventeen".