215550 has 36 divisors (see below), whose sum is σ = 580320. Its totient is φ = 57360.

The previous prime is 215531. The next prime is 215563. The reversal of 215550 is 55512.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 211 + ... + 689.

It is an arithmetic number, because the mean of its divisors is an integer number (16120).

2²¹⁵⁵⁵⁰ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 215550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (290160).

215550 is an abundant number, since it is smaller than the sum of its proper divisors (364770).

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

215550 is a wasteful number, since it uses less digits than its factorization.

215550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 497 (or 489 counting only the distinct ones).

The product of its (nonzero) digits is 250, while the sum is 18.

The square root of 215550 is about 464.2736262163. The cubic root of 215550 is about 59.9583043646.

The spelling of 215550 in words is "two hundred fifteen thousand, five hundred fifty".