2166955985 has 16 divisors (see below), whose sum is σ = 2803973760. Its totient is φ = 1602264960.

The previous prime is 2166955979. The next prime is 2166955991. The reversal of 2166955985 is 5895596612.

It is an interprime number because it is at equal distance from previous prime (2166955979) and next prime (2166955991).

It is not a de Polignac number, because 2166955985 - 2⁴ = 2166955969 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2166955985.

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, 274277 + ... + 282066.

It is an arithmetic number, because the mean of its divisors is an integer number (175248360).

Almost surely, 2^2166955985 is an apocalyptic number.

It is an amenable number.

2166955985 is a deficient number, since it is larger than the sum of its proper divisors (637017775).

2166955985 is a wasteful number, since it uses less digits than its factorization.

2166955985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 556408.

The product of its digits is 5832000, while the sum is 56.

The square root of 2166955985 is about 46550.5744862510. The cubic root of 2166955985 is about 1294.0469396753.

The spelling of 2166955985 in words is "two billion, one hundred sixty-six million, nine hundred fifty-five thousand, nine hundred eighty-five".