72120724 has 24 divisors (see below), whose sum is σ = 136339560. Its totient is φ = 33183744.

The previous prime is 72120721. The next prime is 72120739. The reversal of 72120724 is 42702127.

It can be written as a sum of positive squares in 4 ways, for example, as 176400 + 71944324 = 420^2 + 8482^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72120721) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16392 + ... + 20320.

It is an arithmetic number, because the mean of its divisors is an integer number (5680815).

Almost surely, 2^72120724 is an apocalyptic number.

It is an amenable number.

72120724 is a deficient number, since it is larger than the sum of its proper divisors (64218836).

72120724 is a wasteful number, since it uses less digits than its factorization.

72120724 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4299 (or 4297 counting only the distinct ones).

The product of its (nonzero) digits is 1568, while the sum is 25.

The square root of 72120724 is about 8492.3921247196. The cubic root of 72120724 is about 416.2491496284.

The spelling of 72120724 in words is "seventy-two million, one hundred twenty thousand, seven hundred twenty-four".