57028780665 has 24 divisors (see below), whose sum is σ = 98979840648. Its totient is φ = 30375363840.

The previous prime is 57028780657. The next prime is 57028780709. The reversal of 57028780665 is 56608782075.

57028780665 is a `hidden beast` number, since 570 + 2 + 8 + 7 + 8 + 0 + 6 + 65 = 666.

57028780665 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 10187268624 + 46841512041 = 100932^2 + 216429^2 .

It is not a de Polignac number, because 57028780665 - 2³ = 57028780657 is a prime.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

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, 798414 + ... + 866903.

It is an arithmetic number, because the mean of its divisors is an integer number (4124160027).

Almost surely, 2^57028780665 is an apocalyptic number.

It is an amenable number.

57028780665 is a deficient number, since it is larger than the sum of its proper divisors (41951059983).

57028780665 is a wasteful number, since it uses less digits than its factorization.

57028780665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1666089 (or 1666086 counting only the distinct ones).

The product of its (nonzero) digits is 5644800, while the sum is 54.

The spelling of 57028780665 in words is "fifty-seven billion, twenty-eight million, seven hundred eighty thousand, six hundred sixty-five".