72725621 has 4 divisors (see below), whose sum is σ = 72777600. Its totient is φ = 72673644.

The previous prime is 72725617. The next prime is 72725629. The reversal of 72725621 is 12652727.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 72725621 - 2² = 72725617 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72725629) 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, 23831 + ... + 26708.

It is an arithmetic number, because the mean of its divisors is an integer number (18194400).

Almost surely, 2^72725621 is an apocalyptic number.

It is an amenable number.

72725621 is a deficient number, since it is larger than the sum of its proper divisors (51979).

72725621 is a wasteful number, since it uses less digits than its factorization.

72725621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51978.

The product of its digits is 11760, while the sum is 32.

The square root of 72725621 is about 8527.9318125792. The cubic root of 72725621 is about 417.4096444719.

The spelling of 72725621 in words is "seventy-two million, seven hundred twenty-five thousand, six hundred twenty-one".