2156611 has 4 divisors (see below), whose sum is σ = 2160424. Its totient is φ = 2152800.

The previous prime is 2156599. The next prime is 2156617. The reversal of 2156611 is 1166512.

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 2156611 - 2¹⁷ = 2025539 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2156617) 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, 870 + ... + 2251.

It is an arithmetic number, because the mean of its divisors is an integer number (540106).

2^2156611 is an apocalyptic number.

2156611 is a deficient number, since it is larger than the sum of its proper divisors (3813).

2156611 is an equidigital number, since it uses as much as digits as its factorization.

2156611 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3812.

The product of its digits is 360, while the sum is 22.

The square root of 2156611 is about 1468.5404318574. The cubic root of 2156611 is about 129.1984406512.

Subtracting from 2156611 its reverse (1166512), we obtain a palindrome (990099).

The spelling of 2156611 in words is "two million, one hundred fifty-six thousand, six hundred eleven".