2166778712 has 16 divisors (see below), whose sum is σ = 4643097360. Its totient is φ = 928619424.

The previous prime is 2166778699. The next prime is 2166778721. The reversal of 2166778712 is 2178776612.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19346183 + ... + 19346294.

It is an arithmetic number, because the mean of its divisors is an integer number (290193585).

Almost surely, 2^2166778712 is an apocalyptic number.

It is an amenable number.

2166778712 is an abundant number, since it is smaller than the sum of its proper divisors (2476318648).

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

2166778712 is a wasteful number, since it uses less digits than its factorization.

2166778712 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38692490 (or 38692486 counting only the distinct ones).

The product of its digits is 395136, while the sum is 47.

The square root of 2166778712 is about 46548.6703569500. The cubic root of 2166778712 is about 1294.0116511815.

The spelling of 2166778712 in words is "two billion, one hundred sixty-six million, seven hundred seventy-eight thousand, seven hundred twelve".