2157664560 has 80 divisors (see below), whose sum is σ = 6694285824. Its totient is φ = 574902016.

The previous prime is 2157664559. The next prime is 2157664589. The reversal of 2157664560 is 654667512.

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 362569 + ... + 368471.

Almost surely, 2^2157664560 is an apocalyptic number.

2157664560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2157664560 is an abundant number, since it is smaller than the sum of its proper divisors (4536621264).

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

2157664560 is a wasteful number, since it uses less digits than its factorization.

2157664560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7442 (or 7436 counting only the distinct ones).

The product of its (nonzero) digits is 302400, while the sum is 42.

The square root of 2157664560 is about 46450.6680253363. The cubic root of 2157664560 is about 1292.1947614773.

The spelling of 2157664560 in words is "two billion, one hundred fifty-seven million, six hundred sixty-four thousand, five hundred sixty".