221187 has 8 divisors (see below), whose sum is σ = 312336. Its totient is φ = 138752.

The previous prime is 221173. The next prime is 221197. The reversal of 221187 is 781122.

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

It is a cyclic number.

It is not a de Polignac number, because 221187 - 2⁴ = 221171 is a prime.

It is not an unprimeable number, because it can be changed into a prime (221197) 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, 2118 + ... + 2219.

It is an arithmetic number, because the mean of its divisors is an integer number (39042).

2²²¹¹⁸⁷ is an apocalyptic number.

221187 is a deficient number, since it is larger than the sum of its proper divisors (91149).

221187 is a wasteful number, since it uses less digits than its factorization.

221187 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4357.

The product of its digits is 224, while the sum is 21.

The square root of 221187 is about 470.3052200433. The cubic root of 221187 is about 60.4764838141.

The spelling of 221187 in words is "two hundred twenty-one thousand, one hundred eighty-seven".