72907897 has 4 divisors (see below), whose sum is σ = 72928756. Its totient is φ = 72887040.

The previous prime is 72907867. The next prime is 72907949. The reversal of 72907897 is 79870927.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 23078416 + 49829481 = 4804^2 + 7059^2 .

It is a cyclic number.

It is not a de Polignac number, because 72907897 - 2¹⁵ = 72875129 is a prime.

It is a super-2 number, since 2×72907897² = 10631122889925218, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 72907897.

It is not an unprimeable number, because it can be changed into a prime (72907837) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3768 + ... + 12649.

It is an arithmetic number, because the mean of its divisors is an integer number (18232189).

Almost surely, 2^72907897 is an apocalyptic number.

It is an amenable number.

72907897 is a deficient number, since it is larger than the sum of its proper divisors (20859).

72907897 is a wasteful number, since it uses less digits than its factorization.

72907897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20858.

The product of its (nonzero) digits is 444528, while the sum is 49.

The square root of 72907897 is about 8538.6121237588. The cubic root of 72907897 is about 417.7580786892.

The spelling of 72907897 in words is "seventy-two million, nine hundred seven thousand, eight hundred ninety-seven".