304220921 has 2 divisors, whose sum is σ = 304220922. Its totient is φ = 304220920.

The previous prime is 304220897. The next prime is 304220927. The reversal of 304220921 is 129022403.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 298045696 + 6175225 = 17264^2 + 2485^2 .

It is a cyclic number.

It is not a de Polignac number, because 304220921 - 2¹⁰ = 304219897 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (304220927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 152110460 + 152110461.

It is an arithmetic number, because the mean of its divisors is an integer number (152110461).

Almost surely, 2^304220921 is an apocalyptic number.

It is an amenable number.

304220921 is a deficient number, since it is larger than the sum of its proper divisors (1).

304220921 is an equidigital number, since it uses as much as digits as its factorization.

304220921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 304220921 is about 17441.9299677530. The cubic root of 304220921 is about 672.5579215185.

The spelling of 304220921 in words is "three hundred four million, two hundred twenty thousand, nine hundred twenty-one".