311221343 has 2 divisors, whose sum is σ = 311221344. Its totient is φ = 311221342.

The previous prime is 311221331. The next prime is 311221373. The reversal of 311221343 is 343122113.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 311221343 - 2²⁸ = 42785887 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (311221373) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 155610671 + 155610672.

It is an arithmetic number, because the mean of its divisors is an integer number (155610672).

Almost surely, 2^311221343 is an apocalyptic number.

311221343 is a deficient number, since it is larger than the sum of its proper divisors (1).

311221343 is an equidigital number, since it uses as much as digits as its factorization.

311221343 is an evil number, because the sum of its binary digits is even.

The product of its digits is 432, while the sum is 20.

The square root of 311221343 is about 17641.4665773569. The cubic root of 311221343 is about 677.6775898245.

Adding to 311221343 its reverse (343122113), we get a palindrome (654343456).

The spelling of 311221343 in words is "three hundred eleven million, two hundred twenty-one thousand, three hundred forty-three".