72531613536 has 48 divisors (see below), whose sum is σ = 200416305600. Its totient is φ = 22904719488.

The previous prime is 72531613507. The next prime is 72531613541. The reversal of 72531613536 is 63531613527.

It is a tau number, because it is divible by the number of its divisors (48).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19880746 + ... + 19884393.

It is an arithmetic number, because the mean of its divisors is an integer number (4175339700).

Almost surely, 2^72531613536 is an apocalyptic number.

72531613536 is a gapful number since it is divisible by the number (76) formed by its first and last digit.

It is an amenable number.

72531613536 is an abundant number, since it is smaller than the sum of its proper divisors (127884692064).

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

72531613536 is a wasteful number, since it uses less digits than its factorization.

72531613536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39765171 (or 39765163 counting only the distinct ones).

The product of its digits is 340200, while the sum is 42.

Subtracting from 72531613536 its reverse (63531613527), we obtain a palindrome (9000000009).

The spelling of 72531613536 in words is "seventy-two billion, five hundred thirty-one million, six hundred thirteen thousand, five hundred thirty-six".