72813856 has 48 divisors (see below), whose sum is σ = 153049176. Its totient is φ = 33980416.

The previous prime is 72813787. The next prime is 72813863. The reversal of 72813856 is 65831827.

It can be written as a sum of positive squares in 4 ways, for example, as 72522256 + 291600 = 8516^2 + 540^2 .

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, 74040 + ... + 75016.

Almost surely, 2^72813856 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 72813856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (76524588).

72813856 is an abundant number, since it is smaller than the sum of its proper divisors (80235320).

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

72813856 is a wasteful number, since it uses less digits than its factorization.

72813856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1141 (or 1133 counting only the distinct ones).

The product of its digits is 80640, while the sum is 40.

The square root of 72813856 is about 8533.1035385726. The cubic root of 72813856 is about 417.5783848904.

The spelling of 72813856 in words is "seventy-two million, eight hundred thirteen thousand, eight hundred fifty-six".