56661555 has 32 divisors (see below), whose sum is σ = 93312000. Its totient is φ = 29345792.

The previous prime is 56661547. The next prime is 56661557. The reversal of 56661555 is 55516665.

It is a cyclic number.

It is not a de Polignac number, because 56661555 - 2³ = 56661547 is a prime.

It is not an unprimeable number, because it can be changed into a prime (56661557) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 125971 + ... + 126419.

It is an arithmetic number, because the mean of its divisors is an integer number (2916000).

Almost surely, 2^56661555 is an apocalyptic number.

56661555 is a deficient number, since it is larger than the sum of its proper divisors (36650445).

56661555 is a wasteful number, since it uses less digits than its factorization.

56661555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 683.

The product of its digits is 135000, while the sum is 39.

The square root of 56661555 is about 7527.3869968270. The cubic root of 56661555 is about 384.0869011765.

The spelling of 56661555 in words is "fifty-six million, six hundred sixty-one thousand, five hundred fifty-five".