2121665360 has 80 divisors (see below), whose sum is σ = 5161169664. Its totient is φ = 809588736.

The previous prime is 2121665353. The next prime is 2121665387. The reversal of 2121665360 is 635661212.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 795389 + ... + 798051.

Almost surely, 2^2121665360 is an apocalyptic number.

2121665360 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 2121665360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2580584832).

2121665360 is an abundant number, since it is smaller than the sum of its proper divisors (3039504304).

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

2121665360 is a wasteful number, since it uses less digits than its factorization.

2121665360 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3132 (or 3126 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 32.

The square root of 2121665360 is about 46061.5388366477. The cubic root of 2121665360 is about 1284.9679492579.

The spelling of 2121665360 in words is "two billion, one hundred twenty-one million, six hundred sixty-five thousand, three hundred sixty".