72245540 has 12 divisors (see below), whose sum is σ = 151715676. Its totient is φ = 28898208.

The previous prime is 72245521. The next prime is 72245549. The reversal of 72245540 is 4554227.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 45454564 + 26790976 = 6742^2 + 5176^2 .

It is not an unprimeable number, because it can be changed into a prime (72245549) 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, 1806119 + ... + 1806158.

It is an arithmetic number, because the mean of its divisors is an integer number (12642973).

Almost surely, 2^72245540 is an apocalyptic number.

It is an amenable number.

72245540 is an abundant number, since it is smaller than the sum of its proper divisors (79470136).

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

72245540 is a wasteful number, since it uses less digits than its factorization.

72245540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3612286 (or 3612284 counting only the distinct ones).

The product of its (nonzero) digits is 11200, while the sum is 29.

The square root of 72245540 is about 8499.7376430099. The cubic root of 72245540 is about 416.4891389499.

Adding to 72245540 its reverse (4554227), we get a palindrome (76799767).

The spelling of 72245540 in words is "seventy-two million, two hundred forty-five thousand, five hundred forty".