2157171 has 4 divisors (see below), whose sum is σ = 2876232. Its totient is φ = 1438112.

The previous prime is 2157163. The next prime is 2157173. The reversal of 2157171 is 1717512.

It is a happy number.

2157171 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 2157171 - 2³ = 2157163 is a prime.

It is a D-number.

2157171 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (2157173) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 359526 + ... + 359531.

It is an arithmetic number, because the mean of its divisors is an integer number (719058).

2^2157171 is an apocalyptic number.

2157171 is a deficient number, since it is larger than the sum of its proper divisors (719061).

2157171 is an equidigital number, since it uses as much as digits as its factorization.

2157171 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 719060.

The product of its digits is 490, while the sum is 24.

The square root of 2157171 is about 1468.7310849846. The cubic root of 2157171 is about 129.2096225265.

The spelling of 2157171 in words is "two million, one hundred fifty-seven thousand, one hundred seventy-one".