221292 has 30 divisors (see below), whose sum is σ = 579348. Its totient is φ = 73656.

The previous prime is 221281. The next prime is 221303. The reversal of 221292 is 292122.

It is an interprime number because it is at equal distance from previous prime (221281) and next prime (221303).

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

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 18 + ... + 665.

2²²¹²⁹² is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221292, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (289674).

221292 is an abundant number, since it is smaller than the sum of its proper divisors (358056).

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

221292 is a wasteful number, since it uses less digits than its factorization.

221292 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 699 (or 688 counting only the distinct ones).

The product of its digits is 144, while the sum is 18.

The square root of 221292 is about 470.4168364334. The cubic root of 221292 is about 60.4860519265.

It can be divided in two parts, 2212 and 92, that added together give a square (2304 = 48²).

The spelling of 221292 in words is "two hundred twenty-one thousand, two hundred ninety-two".