72313440 has 96 divisors (see below), whose sum is σ = 230791680. Its totient is φ = 19029504.

The previous prime is 72313399. The next prime is 72313453. The reversal of 72313440 is 4431327.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 72313440.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 36967 + ... + 38873.

It is an arithmetic number, because the mean of its divisors is an integer number (2404080).

Almost surely, 2^72313440 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 72313440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (115395840).

72313440 is an abundant number, since it is smaller than the sum of its proper divisors (158478240).

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

72313440 is a wasteful number, since it uses less digits than its factorization.

72313440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2004 (or 1996 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 24.

The square root of 72313440 is about 8503.7309458849. The cubic root of 72313440 is about 416.6195772562.

Adding to 72313440 its reverse (4431327), we get a palindrome (76744767).

The spelling of 72313440 in words is "seventy-two million, three hundred thirteen thousand, four hundred forty".