2157115100 has 72 divisors (see below), whose sum is σ = 5404966560. Its totient is φ = 731934720.

The previous prime is 2157114959. The next prime is 2157115109. The reversal of 2157115100 is 15117512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2157115109) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 52016 + ... + 83784.

It is an arithmetic number, because the mean of its divisors is an integer number (75068980).

Almost surely, 2^2157115100 is an apocalyptic number.

2157115100 is a gapful number since it is divisible by the number (20) 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 2157115100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2702483280).

2157115100 is an abundant number, since it is smaller than the sum of its proper divisors (3247851460).

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

2157115100 is a wasteful number, since it uses less digits than its factorization.

2157115100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31887 (or 31880 counting only the distinct ones).

The product of its (nonzero) digits is 350, while the sum is 23.

The square root of 2157115100 is about 46444.7532020572. The cubic root of 2157115100 is about 1292.0850642265.

The spelling of 2157115100 in words is "two billion, one hundred fifty-seven million, one hundred fifteen thousand, one hundred".