218450221 has 8 divisors (see below), whose sum is σ = 252327744. Its totient is φ = 186909120.

The previous prime is 218450209. The next prime is 218450261. The reversal of 218450221 is 122054812.

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 218450221 - 2⁵ = 218450189 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218450261) 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, 583905 + ... + 584278.

It is an arithmetic number, because the mean of its divisors is an integer number (31540968).

Almost surely, 2^218450221 is an apocalyptic number.

It is an amenable number.

218450221 is a deficient number, since it is larger than the sum of its proper divisors (33877523).

218450221 is a wasteful number, since it uses less digits than its factorization.

218450221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1168211.

The product of its (nonzero) digits is 1280, while the sum is 25.

The square root of 218450221 is about 14780.0616033899. The cubic root of 218450221 is about 602.2601982966.

The spelling of 218450221 in words is "two hundred eighteen million, four hundred fifty thousand, two hundred twenty-one".