221218199 has 4 divisors (see below), whose sum is σ = 224967720. Its totient is φ = 217468680.

The previous prime is 221218189. The next prime is 221218211. The reversal of 221218199 is 991812122.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 221218199 - 2⁴ = 221218183 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 (221218189) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1874672 + ... + 1874789.

It is an arithmetic number, because the mean of its divisors is an integer number (56241930).

Almost surely, 2^221218199 is an apocalyptic number.

221218199 is a deficient number, since it is larger than the sum of its proper divisors (3749521).

221218199 is an equidigital number, since it uses as much as digits as its factorization.

221218199 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3749520.

The product of its digits is 5184, while the sum is 35.

The square root of 221218199 is about 14873.4057633079. The cubic root of 221218199 is about 604.7932713537.

The spelling of 221218199 in words is "two hundred twenty-one million, two hundred eighteen thousand, one hundred ninety-nine".