2157216280 has 16 divisors (see below), whose sum is σ = 4853736720. Its totient is φ = 862886496.

The previous prime is 2157216263. The next prime is 2157216289. The reversal of 2157216280 is 826127512.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2157216289) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26965164 + ... + 26965243.

It is an arithmetic number, because the mean of its divisors is an integer number (303358545).

Almost surely, 2^2157216280 is an apocalyptic number.

2157216280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2157216280 is an abundant number, since it is smaller than the sum of its proper divisors (2696520440).

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

2157216280 is a wasteful number, since it uses less digits than its factorization.

2157216280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53930418 (or 53930414 counting only the distinct ones).

The product of its (nonzero) digits is 13440, while the sum is 34.

The square root of 2157216280 is about 46445.8424404166. The cubic root of 2157216280 is about 1292.1052657637.

The spelling of 2157216280 in words is "two billion, one hundred fifty-seven million, two hundred sixteen thousand, two hundred eighty".