2180891 has 4 divisors (see below), whose sum is σ = 2239872. Its totient is φ = 2121912.

The previous prime is 2180873. The next prime is 2180911. The reversal of 2180891 is 1980812.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2180891 - 2¹⁰ = 2179867 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2180491) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29435 + ... + 29508.

It is an arithmetic number, because the mean of its divisors is an integer number (559968).

2^2180891 is an apocalyptic number.

2180891 is a deficient number, since it is larger than the sum of its proper divisors (58981).

2180891 is an equidigital number, since it uses as much as digits as its factorization.

2180891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58980.

The product of its (nonzero) digits is 1152, while the sum is 29.

The square root of 2180891 is about 1476.7840058722. The cubic root of 2180891 is about 129.6814885006.

The spelling of 2180891 in words is "two million, one hundred eighty thousand, eight hundred ninety-one".