72944640 has 132 divisors (see below), whose sum is σ = 252910944. Its totient is φ = 19439616.

The previous prime is 72944587. The next prime is 72944687. The reversal of 72944640 is 4644927.

72944640 is a `hidden beast` number, since 7 + 2 + 9 + 4 + 4 + 640 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 72944595 and 72944604.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 45289 + ... + 46871.

It is an arithmetic number, because the mean of its divisors is an integer number (1915992).

Almost surely, 2^72944640 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 72944640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (126455472).

72944640 is an abundant number, since it is smaller than the sum of its proper divisors (179966304).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

72944640 is a wasteful number, since it uses less digits than its factorization.

72944640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1614 (or 1593 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 36.

The square root of 72944640 is about 8540.7634319187. The cubic root of 72944640 is about 417.8282453326.

It can be divided in two parts, 729 and 44640, that added together give a square (45369 = 213²).

The spelling of 72944640 in words is "seventy-two million, nine hundred forty-four thousand, six hundred forty".