2166212520 has 48 divisors (see below), whose sum is σ = 7040191860. Its totient is φ = 577656576.

The previous prime is 2166212509. The next prime is 2166212533. The reversal of 2166212520 is 252126612.

2166212520 is a `hidden beast` number, since 2 + 16 + 621 + 2 + 5 + 20 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 2166157764 + 54756 = 46542^2 + 234^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3008269 + ... + 3008988.

Almost surely, 2^2166212520 is an apocalyptic number.

2166212520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2166212520 is an abundant number, since it is smaller than the sum of its proper divisors (4873979340).

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

2166212520 is a wasteful number, since it uses less digits than its factorization.

2166212520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6017274 (or 6017267 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 2166212520 is about 46542.5882391601. The cubic root of 2166212520 is about 1293.8989304152.

The spelling of 2166212520 in words is "two billion, one hundred sixty-six million, two hundred twelve thousand, five hundred twenty".