2157365728 has 120 divisors (see below), whose sum is σ = 5077899288. Its totient is φ = 901700352.

The previous prime is 2157365701. The next prime is 2157365729. The reversal of 2157365728 is 8275637512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2157365729) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 3303450 + ... + 3304102.

Almost surely, 2^2157365728 is an apocalyptic number.

2157365728 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2157365728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2538949644).

2157365728 is an abundant number, since it is smaller than the sum of its proper divisors (2920533560).

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

2157365728 is an frugal number, since it uses more digits than its factorization.

2157365728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 734 (or 705 counting only the distinct ones).

The product of its digits is 705600, while the sum is 46.

The square root of 2157365728 is about 46447.4512540785. The cubic root of 2157365728 is about 1292.1351033049.

The spelling of 2157365728 in words is "two billion, one hundred fifty-seven million, three hundred sixty-five thousand, seven hundred twenty-eight".