72855770 has 32 divisors (see below), whose sum is σ = 144683280. Its totient is φ = 26242560.

The previous prime is 72855767. The next prime is 72855779. The reversal of 72855770 is 7755827.

It can be written as a sum of positive squares in 8 ways, for example, as 9541921 + 63313849 = 3089^2 + 7957^2 .

It is a Smith number, since the sum of its digits (41) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is not an unprimeable number, because it can be changed into a prime (72855779) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1505 + ... + 12164.

Almost surely, 2^72855770 is an apocalyptic number.

72855770 is a deficient number, since it is larger than the sum of its proper divisors (71827510).

72855770 is a wasteful number, since it uses less digits than its factorization.

72855770 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13730.

The product of its (nonzero) digits is 137200, while the sum is 41.

The square root of 72855770 is about 8535.5591498156. The cubic root of 72855770 is about 417.6584933759.

The spelling of 72855770 in words is "seventy-two million, eight hundred fifty-five thousand, seven hundred seventy".