311221223 has 2 divisors, whose sum is σ = 311221224. Its totient is φ = 311221222.

The previous prime is 311221213. The next prime is 311221237. The reversal of 311221223 is 322122113.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 311221223 - 2¹⁸ = 310959079 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (311221213) 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, 155610611 + 155610612.

It is an arithmetic number, because the mean of its divisors is an integer number (155610612).

Almost surely, 2^311221223 is an apocalyptic number.

311221223 is a deficient number, since it is larger than the sum of its proper divisors (1).

311221223 is an equidigital number, since it uses as much as digits as its factorization.

311221223 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 144, while the sum is 17.

The square root of 311221223 is about 17641.4631762788. The cubic root of 311221223 is about 677.6775027254.

Adding to 311221223 its reverse (322122113), we get a palindrome (633343336).

The spelling of 311221223 in words is "three hundred eleven million, two hundred twenty-one thousand, two hundred twenty-three".