2171868 has 36 divisors (see below), whose sum is σ = 5309640. Its totient is φ = 690144.

The previous prime is 2171857. The next prime is 2171881. The reversal of 2171868 is 8681712.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 27453 + ... + 27531.

It is an arithmetic number, because the mean of its divisors is an integer number (147490).

2^2171868 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2171868, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2654820).

2171868 is an abundant number, since it is smaller than the sum of its proper divisors (3137772).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2171868 is a wasteful number, since it uses less digits than its factorization.

2171868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 194 (or 113 counting only the distinct ones).

The product of its digits is 5376, while the sum is 33.

The square root of 2171868 is about 1473.7258903880. The cubic root of 2171868 is about 129.5023975545.

The spelling of 2171868 in words is "two million, one hundred seventy-one thousand, eight hundred sixty-eight".