2156555 has 4 divisors (see below), whose sum is σ = 2587872. Its totient is φ = 1725240.

The previous prime is 2156537. The next prime is 2156597. The reversal of 2156555 is 5556512.

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

It is not a de Polignac number, because 2156555 - 2⁶ = 2156491 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 215651 + ... + 215660.

It is an arithmetic number, because the mean of its divisors is an integer number (646968).

2^2156555 is an apocalyptic number.

2156555 is a deficient number, since it is larger than the sum of its proper divisors (431317).

2156555 is an equidigital number, since it uses as much as digits as its factorization.

2156555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 431316.

The product of its digits is 7500, while the sum is 29.

The square root of 2156555 is about 1468.5213651834. The cubic root of 2156555 is about 129.1973223573.

The spelling of 2156555 in words is "two million, one hundred fifty-six thousand, five hundred fifty-five".