72115440 has 40 divisors (see below), whose sum is σ = 223558608. Its totient is φ = 19230720.

The previous prime is 72115423. The next prime is 72115441. The reversal of 72115440 is 4451127.

It is a tau number, because it is divible by the number of its divisors (40).

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 72115440.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72115441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 150001 + ... + 150480.

Almost surely, 2^72115440 is an apocalyptic number.

It is an amenable number.

72115440 is an abundant number, since it is smaller than the sum of its proper divisors (151443168).

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

72115440 is a wasteful number, since it uses less digits than its factorization.

72115440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 300497 (or 300491 counting only the distinct ones).

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

The square root of 72115440 is about 8492.0810170417. The cubic root of 72115440 is about 416.2389837375.

Adding to 72115440 its reverse (4451127), we get a palindrome (76566567).

It can be divided in two parts, 721 and 15440, that added together give a palindrome (16161).

The spelling of 72115440 in words is "seventy-two million, one hundred fifteen thousand, four hundred forty".