57156021 has 12 divisors (see below), whose sum is σ = 88909548. Its totient is φ = 35172864.

The previous prime is 57156019. The next prime is 57156037. The reversal of 57156021 is 12065175.

57156021 is a `hidden beast` number, since 57 + 1 + 5 + 602 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 35533521 + 21622500 = 5961^2 + 4650^2 .

It is not a de Polignac number, because 57156021 - 2¹ = 57156019 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (57156061) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 244140 + ... + 244373.

It is an arithmetic number, because the mean of its divisors is an integer number (7409129).

Almost surely, 2^57156021 is an apocalyptic number.

It is an amenable number.

57156021 is a deficient number, since it is larger than the sum of its proper divisors (31753527).

57156021 is a wasteful number, since it uses less digits than its factorization.

57156021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 488532 (or 488529 counting only the distinct ones).

The product of its (nonzero) digits is 2100, while the sum is 27.

The square root of 57156021 is about 7560.1601173520. The cubic root of 57156021 is about 385.2009318275.

The spelling of 57156021 in words is "fifty-seven million, one hundred fifty-six thousand, twenty-one".