2155980860 has 24 divisors (see below), whose sum is σ = 4939156656. Its totient is φ = 783992960.

The previous prime is 2155980821. The next prime is 2155980887. The reversal of 2155980860 is 680895512.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4899737 + ... + 4900176.

It is an arithmetic number, because the mean of its divisors is an integer number (205798194).

Almost surely, 2^2155980860 is an apocalyptic number.

2155980860 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2155980860 is an abundant number, since it is smaller than the sum of its proper divisors (2783175796).

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

2155980860 is a wasteful number, since it uses less digits than its factorization.

2155980860 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9799933 (or 9799931 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 44.

The square root of 2155980860 is about 46432.5409599776. The cubic root of 2155980860 is about 1291.8585593135.

The spelling of 2155980860 in words is "two billion, one hundred fifty-five million, nine hundred eighty thousand, eight hundred sixty".