215944 has 8 divisors (see below), whose sum is σ = 404910. Its totient is φ = 107968.

The previous prime is 215939. The next prime is 215953. The reversal of 215944 is 449512.

It can be written as a sum of positive squares in only one way, i.e., 213444 + 2500 = 462^2 + 50^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×215944² = 93263622272, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

215944 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13489 + ... + 13504.

2²¹⁵⁹⁴⁴ is an apocalyptic number.

It is an amenable number.

215944 is a deficient number, since it is larger than the sum of its proper divisors (188966).

215944 is a wasteful number, since it uses less digits than its factorization.

215944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26999 (or 26995 counting only the distinct ones).

The product of its digits is 1440, while the sum is 25.

The square root of 215944 is about 464.6977512319. The cubic root of 215944 is about 59.9948143666.

The spelling of 215944 in words is "two hundred fifteen thousand, nine hundred forty-four".