72144040 has 32 divisors (see below), whose sum is σ = 162648360. Its totient is φ = 28800000.

The previous prime is 72144019. The next prime is 72144047. The reversal of 72144040 is 4044127.

It can be written as a sum of positive squares in 4 ways, for example, as 67469796 + 4674244 = 8214^2 + 2162^2 .

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (72144047) 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, 22540 + ... + 25540.

Almost surely, 2^72144040 is an apocalyptic number.

It is an amenable number.

72144040 is an abundant number, since it is smaller than the sum of its proper divisors (90504320).

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

72144040 is a wasteful number, since it uses less digits than its factorization.

72144040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3613 (or 3609 counting only the distinct ones).

The product of its (nonzero) digits is 896, while the sum is 22.

The square root of 72144040 is about 8493.7647718783. The cubic root of 72144040 is about 416.2940013665.

Adding to 72144040 its reverse (4044127), we get a palindrome (76188167).

The spelling of 72144040 in words is "seventy-two million, one hundred forty-four thousand, forty".