2145644660 has 24 divisors (see below), whose sum is σ = 4506969600. Its totient is φ = 858045344.

The previous prime is 2145644651. The next prime is 2145644693. The reversal of 2145644660 is 664465412.

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, 88541 + ... + 110139.

It is an arithmetic number, because the mean of its divisors is an integer number (187790400).

Almost surely, 2^2145644660 is an apocalyptic number.

2145644660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2145644660 is an abundant number, since it is smaller than the sum of its proper divisors (2361324940).

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

2145644660 is a wasteful number, since it uses less digits than its factorization.

2145644660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26575 (or 26573 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 38.

The square root of 2145644660 is about 46321.1038296801. The cubic root of 2145644660 is about 1289.7907759151.

The spelling of 2145644660 in words is "two billion, one hundred forty-five million, six hundred forty-four thousand, six hundred sixty".