2118861 has 12 divisors (see below), whose sum is σ = 3221920. Its totient is φ = 1338120.

The previous prime is 2118841. The next prime is 2118871. The reversal of 2118861 is 1688112.

It is not a de Polignac number, because 2118861 - 2⁷ = 2118733 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2118811) 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, 6025 + ... + 6366.

2^2118861 is an apocalyptic number.

It is an amenable number.

2118861 is a deficient number, since it is larger than the sum of its proper divisors (1103059).

2118861 is a wasteful number, since it uses less digits than its factorization.

2118861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12416 (or 12413 counting only the distinct ones).

The product of its digits is 768, while the sum is 27.

The square root of 2118861 is about 1455.6307911005. The cubic root of 2118861 is about 128.4401554320.

The spelling of 2118861 in words is "two million, one hundred eighteen thousand, eight hundred sixty-one".