221450209 has 4 divisors (see below), whose sum is σ = 224755504. Its totient is φ = 218144916.

The previous prime is 221450189. The next prime is 221450221. The reversal of 221450209 is 902054122.

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.

It is a cyclic number.

It is not a de Polignac number, because 221450209 - 2¹⁹ = 220925921 is a prime.

It is a super-2 number, since 2×221450209² = 98080390132287362, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221450249) 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, 1652547 + ... + 1652680.

It is an arithmetic number, because the mean of its divisors is an integer number (56188876).

Almost surely, 2^221450209 is an apocalyptic number.

It is an amenable number.

221450209 is a deficient number, since it is larger than the sum of its proper divisors (3305295).

221450209 is an equidigital number, since it uses as much as digits as its factorization.

221450209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3305294.

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 221450209 is about 14881.2032107622. The cubic root of 221450209 is about 605.0046298851.

The spelling of 221450209 in words is "two hundred twenty-one million, four hundred fifty thousand, two hundred nine".