221289 has 8 divisors (see below), whose sum is σ = 312480. Its totient is φ = 138816.

The previous prime is 221281. The next prime is 221303. The reversal of 221289 is 982122.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 221289 - 2³ = 221281 is a prime.

It is an Ulam number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (221281) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2119 + ... + 2220.

It is an arithmetic number, because the mean of its divisors is an integer number (39060).

2²²¹²⁸⁹ is an apocalyptic number.

It is an amenable number.

221289 is a deficient number, since it is larger than the sum of its proper divisors (91191).

221289 is a wasteful number, since it uses less digits than its factorization.

221289 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4359.

The product of its digits is 576, while the sum is 24.

The square root of 221289 is about 470.4136477612. The cubic root of 221289 is about 60.4857785939.

The spelling of 221289 in words is "two hundred twenty-one thousand, two hundred eighty-nine".