209469221 has 4 divisors (see below), whose sum is σ = 225582252. Its totient is φ = 193356192.

The previous prime is 209469209. The next prime is 209469251. The reversal of 209469221 is 122964902.

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

It can be written as a sum of positive squares in 2 ways, for example, as 16564900 + 192904321 = 4070^2 + 13889^2 .

It is a cyclic number.

It is not a de Polignac number, because 209469221 - 2⁶ = 209469157 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 (209469251) 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, 8056496 + ... + 8056521.

It is an arithmetic number, because the mean of its divisors is an integer number (56395563).

Almost surely, 2^209469221 is an apocalyptic number.

It is an amenable number.

209469221 is a deficient number, since it is larger than the sum of its proper divisors (16113031).

209469221 is a wasteful number, since it uses less digits than its factorization.

209469221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16113030.

The product of its (nonzero) digits is 15552, while the sum is 35.

The square root of 209469221 is about 14473.0515441630. The cubic root of 209469221 is about 593.8909935748.

The spelling of 209469221 in words is "two hundred nine million, four hundred sixty-nine thousand, two hundred twenty-one".