312303221 has 2 divisors, whose sum is σ = 312303222. Its totient is φ = 312303220.

The previous prime is 312303217. The next prime is 312303239. The reversal of 312303221 is 122303213.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 250114225 + 62188996 = 15815^2 + 7886^2 .

It is a cyclic number.

It is not a de Polignac number, because 312303221 - 2² = 312303217 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 312303221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (312303241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 156151610 + 156151611.

It is an arithmetic number, because the mean of its divisors is an integer number (156151611).

Almost surely, 2^312303221 is an apocalyptic number.

It is an amenable number.

312303221 is a deficient number, since it is larger than the sum of its proper divisors (1).

312303221 is an equidigital number, since it uses as much as digits as its factorization.

312303221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 216, while the sum is 17.

The square root of 312303221 is about 17672.1029025976. The cubic root of 312303221 is about 678.4619368052.

Adding to 312303221 its reverse (122303213), we get a palindrome (434606434).

The spelling of 312303221 in words is "three hundred twelve million, three hundred three thousand, two hundred twenty-one".