2187871 has 4 divisors (see below), whose sum is σ = 2500432. Its totient is φ = 1875312.

The previous prime is 2187863. The next prime is 2187877. The reversal of 2187871 is 1787812.

2187871 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 2187871 - 2³ = 2187863 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 (2187877) 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, 156270 + ... + 156283.

It is an arithmetic number, because the mean of its divisors is an integer number (625108).

2^2187871 is an apocalyptic number.

2187871 is a deficient number, since it is larger than the sum of its proper divisors (312561).

2187871 is an equidigital number, since it uses as much as digits as its factorization.

2187871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 312560.

The product of its digits is 6272, while the sum is 34.

The square root of 2187871 is about 1479.1453613489. The cubic root of 2187871 is about 129.8196908564.

It can be divided in two parts, 218 and 7871, that multiplied together give a triangular number (1715878 = T₁₈₅₂).

The spelling of 2187871 in words is "two million, one hundred eighty-seven thousand, eight hundred seventy-one".