2168566920 has 384 divisors, whose sum is σ = 8148198240. Its totient is φ = 495452160.

The previous prime is 2168566913. The next prime is 2168566931. The reversal of 2168566920 is 296658612.

2168566920 is a `hidden beast` number, since 2 + 1 + 68 + 566 + 9 + 20 = 666.

It can be written as a sum of positive squares in 16 ways, for example, as 239073444 + 1929493476 = 15462^2 + 43926^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 7717180 + ... + 7717460.

Almost surely, 2^2168566920 is an apocalyptic number.

2168566920 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 2168566920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4074099120).

2168566920 is an abundant number, since it is smaller than the sum of its proper divisors (5979631320).

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

2168566920 is a wasteful number, since it uses less digits than its factorization.

2168566920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 425 (or 418 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The square root of 2168566920 is about 46567.8743341373. The cubic root of 2168566920 is about 1294.3675290424.

The spelling of 2168566920 in words is "two billion, one hundred sixty-eight million, five hundred sixty-six thousand, nine hundred twenty".