199109221 has 4 divisors (see below), whose sum is σ = 203739712. Its totient is φ = 194478732.

The previous prime is 199109201. The next prime is 199109233. The reversal of 199109221 is 122901991.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 122901991 = 1949 ⋅63059.

It is a cyclic number.

It is not a de Polignac number, because 199109221 - 2¹⁵ = 199076453 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 (199109201) 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, 2315181 + ... + 2315266.

It is an arithmetic number, because the mean of its divisors is an integer number (50934928).

Almost surely, 2^199109221 is an apocalyptic number.

It is an amenable number.

199109221 is a deficient number, since it is larger than the sum of its proper divisors (4630491).

199109221 is an equidigital number, since it uses as much as digits as its factorization.

199109221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4630490.

The product of its (nonzero) digits is 2916, while the sum is 34.

The square root of 199109221 is about 14110.6066843350. The cubic root of 199109221 is about 583.9340375943.

The spelling of 199109221 in words is "one hundred ninety-nine million, one hundred nine thousand, two hundred twenty-one".