2161087500 has 432 divisors, whose sum is σ = 7685508096. Its totient is φ = 468000000.

The previous prime is 2161087483. The next prime is 2161087559. The reversal of 2161087500 is 57801612.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 69712485 + ... + 69712515.

It is an arithmetic number, because the mean of its divisors is an integer number (17790528).

Almost surely, 2^2161087500 is an apocalyptic number.

2161087500 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 2161087500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3842754048).

2161087500 is an abundant number, since it is smaller than the sum of its proper divisors (5524420596).

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

2161087500 is a wasteful number, since it uses less digits than its factorization.

2161087500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 100 (or 65 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 30.

The square root of 2161087500 is about 46487.4983194407. The cubic root of 2161087500 is about 1292.8777172258.

The spelling of 2161087500 in words is "two billion, one hundred sixty-one million, eighty-seven thousand, five hundred".