72121245 has 32 divisors (see below), whose sum is σ = 138823680. Its totient is φ = 31233600.

The previous prime is 72121237. The next prime is 72121271. The reversal of 72121245 is 54212127.

It is not a de Polignac number, because 72121245 - 2³ = 72121237 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 16081 + ... + 20070.

It is an arithmetic number, because the mean of its divisors is an integer number (4338240).

Almost surely, 2^72121245 is an apocalyptic number.

It is an amenable number.

72121245 is a deficient number, since it is larger than the sum of its proper divisors (66702435).

72121245 is a wasteful number, since it uses less digits than its factorization.

72121245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36185.

The product of its digits is 1120, while the sum is 24.

The square root of 72121245 is about 8492.4227991781. The cubic root of 72121245 is about 416.2501519537.

The spelling of 72121245 in words is "seventy-two million, one hundred twenty-one thousand, two hundred forty-five".