215655 has 16 divisors (see below), whose sum is σ = 376704. Its totient is φ = 104480.

The previous prime is 215653. The next prime is 215659. The reversal of 215655 is 556512.

215655 = T₁₀ + T₁₁ + ... + T₁₀₈.

It is not a de Polignac number, because 215655 - 2¹ = 215653 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215653) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 489 + ... + 818.

It is an arithmetic number, because the mean of its divisors is an integer number (23544).

2²¹⁵⁶⁵⁵ is an apocalyptic number.

215655 is a deficient number, since it is larger than the sum of its proper divisors (161049).

215655 is a wasteful number, since it uses less digits than its factorization.

215655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1326.

The product of its digits is 1500, while the sum is 24.

The square root of 215655 is about 464.3866923158. The cubic root of 215655 is about 59.9680385330.

It can be divided in two parts, 2156 and 55, that added together give a triangular number (2211 = T₆₆).

The spelling of 215655 in words is "two hundred fifteen thousand, six hundred fifty-five".