221490 has 48 divisors (see below), whose sum is σ = 606528. Its totient is φ = 55968.

The previous prime is 221489. The next prime is 221497. The reversal of 221490 is 94122.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221497) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2017 + ... + 2123.

It is an arithmetic number, because the mean of its divisors is an integer number (12636).

2²²¹⁴⁹⁰ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221490, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (303264).

221490 is an abundant number, since it is smaller than the sum of its proper divisors (385038).

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

221490 is a wasteful number, since it uses less digits than its factorization.

221490 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143 (or 140 counting only the distinct ones).

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

The square root of 221490 is about 470.6272410305. The cubic root of 221490 is about 60.5040864212.

It can be divided in two parts, 2214 and 90, that added together give a square (2304 = 48²).

The spelling of 221490 in words is "two hundred twenty-one thousand, four hundred ninety".