72817225 has 24 divisors (see below), whose sum is σ = 98859992. Its totient is φ = 52876800.

The previous prime is 72817211. The next prime is 72817243. The reversal of 72817225 is 52271827.

It can be written as a sum of positive squares in 12 ways, for example, as 67453369 + 5363856 = 8213^2 + 2316^2 .

It is not a de Polignac number, because 72817225 - 2⁷ = 72817097 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17989 + ... + 21661.

Almost surely, 2^72817225 is an apocalyptic number.

It is an amenable number.

72817225 is a deficient number, since it is larger than the sum of its proper divisors (26042767).

72817225 is a wasteful number, since it uses less digits than its factorization.

72817225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3757 (or 3752 counting only the distinct ones).

The product of its digits is 15680, while the sum is 34.

The square root of 72817225 is about 8533.3009439489. The cubic root of 72817225 is about 417.5848250561.

The spelling of 72817225 in words is "seventy-two million, eight hundred seventeen thousand, two hundred twenty-five".