72172478 has 16 divisors (see below), whose sum is σ = 124016640. Its totient is φ = 30857976.

The previous prime is 72172453. The next prime is 72172481. The reversal of 72172478 is 87427127.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 275 + ... + 12017.

It is an arithmetic number, because the mean of its divisors is an integer number (7751040).

Almost surely, 2^72172478 is an apocalyptic number.

72172478 is a deficient number, since it is larger than the sum of its proper divisors (51844162).

72172478 is a wasteful number, since it uses less digits than its factorization.

72172478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12191.

The product of its digits is 43904, while the sum is 38.

The square root of 72172478 is about 8495.4386584802. The cubic root of 72172478 is about 416.3486929420.

The spelling of 72172478 in words is "seventy-two million, one hundred seventy-two thousand, four hundred seventy-eight".