215844 has 12 divisors (see below), whose sum is σ = 503664. Its totient is φ = 71944.

The previous prime is 215843. The next prime is 215851. The reversal of 215844 is 448512.

It is a tau number, because it is divible by the number of its divisors (12).

It is not an unprimeable number, because it can be changed into a prime (215843) 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, 8982 + ... + 9005.

It is an arithmetic number, because the mean of its divisors is an integer number (41972).

2²¹⁵⁸⁴⁴ is an apocalyptic number.

It is an amenable number.

215844 is an abundant number, since it is smaller than the sum of its proper divisors (287820).

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

215844 is a wasteful number, since it uses less digits than its factorization.

215844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17994 (or 17992 counting only the distinct ones).

The product of its digits is 1280, while the sum is 24.

The square root of 215844 is about 464.5901419531. The cubic root of 215844 is about 59.9855520768.

The spelling of 215844 in words is "two hundred fifteen thousand, eight hundred forty-four".