2157555728 has 20 divisors (see below), whose sum is σ = 4233181440. Its totient is φ = 1065121824.

The previous prime is 2157555713. The next prime is 2157555737. The reversal of 2157555728 is 8275557512.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 852200 + ... + 854727.

It is an arithmetic number, because the mean of its divisors is an integer number (211659072).

Almost surely, 2^2157555728 is an apocalyptic number.

It is an amenable number.

2157555728 is a deficient number, since it is larger than the sum of its proper divisors (2075625712).

2157555728 is a wasteful number, since it uses less digits than its factorization.

2157555728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1707014 (or 1707008 counting only the distinct ones).

The product of its digits is 980000, while the sum is 47.

The square root of 2157555728 is about 46449.4965311789. The cubic root of 2157555728 is about 1292.1730351306.

The spelling of 2157555728 in words is "two billion, one hundred fifty-seven million, five hundred fifty-five thousand, seven hundred twenty-eight".