215915 has 16 divisors (see below), whose sum is σ = 307200. Its totient is φ = 142560.

The previous prime is 215909. The next prime is 215921. The reversal of 215915 is 519512.

It is an interprime number because it is at equal distance from previous prime (215909) and next prime (215921).

It is not a de Polignac number, because 215915 - 2⁴ = 215899 is a prime.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 986 + ... + 1184.

It is an arithmetic number, because the mean of its divisors is an integer number (19200).

2²¹⁵⁹¹⁵ is an apocalyptic number.

215915 is a deficient number, since it is larger than the sum of its proper divisors (91285).

215915 is a wasteful number, since it uses less digits than its factorization.

215915 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 242.

The product of its digits is 450, while the sum is 23.

The square root of 215915 is about 464.6665471066. Note that the first 3 decimals coincide. The cubic root of 215915 is about 59.9921285970.

It can be divided in two parts, 2159 and 15, that multiplied together give a triangular number (32385 = T₂₅₄).

The spelling of 215915 in words is "two hundred fifteen thousand, nine hundred fifteen".