2155664560 has 40 divisors (see below), whose sum is σ = 5727910176. Its totient is φ = 739084800.

The previous prime is 2155664521. The next prime is 2155664591. The reversal of 2155664560 is 654665512.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (40).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1924141 + ... + 1925260.

Almost surely, 2^2155664560 is an apocalyptic number.

2155664560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2155664560 is an abundant number, since it is smaller than the sum of its proper divisors (3572245616).

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

2155664560 is a wasteful number, since it uses less digits than its factorization.

2155664560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3849421 (or 3849415 counting only the distinct ones).

The product of its (nonzero) digits is 216000, while the sum is 40.

The square root of 2155664560 is about 46429.1348185598. The cubic root of 2155664560 is about 1291.7953808234.

The spelling of 2155664560 in words is "two billion, one hundred fifty-five million, six hundred sixty-four thousand, five hundred sixty".