304212221 has 4 divisors (see below), whose sum is σ = 304273500. Its totient is φ = 304150944.

The previous prime is 304212217. The next prime is 304212253. The reversal of 304212221 is 122212403.

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 75446596 + 228765625 = 8686^2 + 15125^2 .

It is a cyclic number.

It is not a de Polignac number, because 304212221 - 2² = 304212217 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 304212221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (304212121) 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, 22466 + ... + 33363.

It is an arithmetic number, because the mean of its divisors is an integer number (76068375).

Almost surely, 2^304212221 is an apocalyptic number.

It is an amenable number.

304212221 is a deficient number, since it is larger than the sum of its proper divisors (61279).

304212221 is an equidigital number, since it uses as much as digits as its factorization.

304212221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61278.

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 304212221 is about 17441.6805669637. The cubic root of 304212221 is about 672.5515102679.

Adding to 304212221 its reverse (122212403), we get a palindrome (426424624).

The spelling of 304212221 in words is "three hundred four million, two hundred twelve thousand, two hundred twenty-one".