2166138 has 24 divisors (see below), whose sum is σ = 5054868. Its totient is φ = 666432.

The previous prime is 2166137. The next prime is 2166161. The reversal of 2166138 is 8316612.

It can be written as a sum of positive squares in 2 ways, for example, as 1734489 + 431649 = 1317^2 + 657^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2166137) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4395 + ... + 4862.

2^2166138 is an apocalyptic number.

2166138 is an abundant number, since it is smaller than the sum of its proper divisors (2888730).

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

2166138 is a wasteful number, since it uses less digits than its factorization.

2166138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9278 (or 9275 counting only the distinct ones).

The product of its digits is 1728, while the sum is 27.

The square root of 2166138 is about 1471.7805542947. The cubic root of 2166138 is about 129.3884093082.

It can be divided in two parts, 2166 and 138, that added together give a square (2304 = 48²).

The spelling of 2166138 in words is "two million, one hundred sixty-six thousand, one hundred thirty-eight".