72531280 has 20 divisors (see below), whose sum is σ = 168635412. Its totient is φ = 29012480.

The previous prime is 72531247. The next prime is 72531281. The reversal of 72531280 is 8213527.

It can be written as a sum of positive squares in 2 ways, for example, as 36675136 + 35856144 = 6056^2 + 5988^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72531281) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 453241 + ... + 453400.

Almost surely, 2^72531280 is an apocalyptic number.

It is an amenable number.

72531280 is an abundant number, since it is smaller than the sum of its proper divisors (96104132).

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

72531280 is a wasteful number, since it uses less digits than its factorization.

72531280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 906654 (or 906648 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 28.

The square root of 72531280 is about 8516.5298097288. The cubic root of 72531280 is about 417.0375052289.

The spelling of 72531280 in words is "seventy-two million, five hundred thirty-one thousand, two hundred eighty".