2157144920 has 128 divisors (see below), whose sum is σ = 5754101760. Its totient is φ = 712212480.

The previous prime is 2157144901. The next prime is 2157144959. The reversal of 2157144920 is 294417512.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2230277 + ... + 2231243.

It is an arithmetic number, because the mean of its divisors is an integer number (44953920).

Almost surely, 2^2157144920 is an apocalyptic number.

2157144920 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 2157144920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2877050880).

2157144920 is an abundant number, since it is smaller than the sum of its proper divisors (3596956840).

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

2157144920 is a wasteful number, since it uses less digits than its factorization.

2157144920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1273 (or 1269 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 35.

The square root of 2157144920 is about 46445.0742275217. The cubic root of 2157144920 is about 1292.0910181352.

The spelling of 2157144920 in words is "two billion, one hundred fifty-seven million, one hundred forty-four thousand, nine hundred twenty".