313221281 has 2 divisors, whose sum is σ = 313221282. Its totient is φ = 313221280.

The previous prime is 313221269. The next prime is 313221299. The reversal of 313221281 is 182122313.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 311204881 + 2016400 = 17641^2 + 1420^2 .

It is a cyclic number.

It is not a de Polignac number, because 313221281 - 2¹⁴ = 313204897 is a prime.

It is a super-2 number, since 2×313221281² = 196215141742561922, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (313229281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 156610640 + 156610641.

It is an arithmetic number, because the mean of its divisors is an integer number (156610641).

Almost surely, 2^313221281 is an apocalyptic number.

It is an amenable number.

313221281 is a deficient number, since it is larger than the sum of its proper divisors (1).

313221281 is an equidigital number, since it uses as much as digits as its factorization.

313221281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 576, while the sum is 23.

The square root of 313221281 is about 17698.0586788495. The cubic root of 313221281 is about 679.1260984078.

Adding to 313221281 its reverse (182122313), we get a palindrome (495343594).

The spelling of 313221281 in words is "three hundred thirteen million, two hundred twenty-one thousand, two hundred eighty-one".