2155871 has 4 divisors (see below), whose sum is σ = 2158992. Its totient is φ = 2152752.

The previous prime is 2155861. The next prime is 2155877. The reversal of 2155871 is 1785512.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2155871 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 (2155877) 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, 11 + ... + 2076.

It is an arithmetic number, because the mean of its divisors is an integer number (539748).

2^2155871 is an apocalyptic number.

2155871 is a deficient number, since it is larger than the sum of its proper divisors (3121).

2155871 is a wasteful number, since it uses less digits than its factorization.

2155871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3120.

The product of its digits is 2800, while the sum is 29.

The square root of 2155871 is about 1468.2884593975. The cubic root of 2155871 is about 129.1836616325.

The spelling of 2155871 in words is "two million, one hundred fifty-five thousand, eight hundred seventy-one".