72057780 has 36 divisors (see below), whose sum is σ = 218575812. Its totient is φ = 19215360.

The previous prime is 72057757. The next prime is 72057803. The reversal of 72057780 is 8775027.

72057780 is a `hidden beast` number, since 7 + 2 + 0 + 577 + 80 = 666.

It is an interprime number because it is at equal distance from previous prime (72057757) and next prime (72057803).

It can be written as a sum of positive squares in 2 ways, for example, as 28259856 + 43797924 = 5316^2 + 6618^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 199981 + ... + 200340.

Almost surely, 2^72057780 is an apocalyptic number.

It is an amenable number.

72057780 is an abundant number, since it is smaller than the sum of its proper divisors (146518032).

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

72057780 is a wasteful number, since it uses less digits than its factorization.

72057780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 400336 (or 400331 counting only the distinct ones).

The product of its (nonzero) digits is 27440, while the sum is 36.

The square root of 72057780 is about 8488.6854105921. The cubic root of 72057780 is about 416.1280193396.

The spelling of 72057780 in words is "seventy-two million, fifty-seven thousand, seven hundred eighty".