72561213522 has 48 divisors (see below), whose sum is σ = 189131991360. Its totient is φ = 19640628576.

The previous prime is 72561213499. The next prime is 72561213539. The reversal of 72561213522 is 22531216527.

72561213522 is a `hidden beast` number, since 7 + 2 + 5 + 6 + 121 + 3 + 522 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 15152413 + ... + 15157200.

It is an arithmetic number, because the mean of its divisors is an integer number (3940249820).

Almost surely, 2^72561213522 is an apocalyptic number.

72561213522 is an abundant number, since it is smaller than the sum of its proper divisors (116570777838).

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

72561213522 is a wasteful number, since it uses less digits than its factorization.

72561213522 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30309647 (or 30309644 counting only the distinct ones).

The product of its digits is 50400, while the sum is 36.

The spelling of 72561213522 in words is "seventy-two billion, five hundred sixty-one million, two hundred thirteen thousand, five hundred twenty-two".