313143221 has 2 divisors, whose sum is σ = 313143222. Its totient is φ = 313143220.

The previous prime is 313143217. The next prime is 313143223. The reversal of 313143221 is 122341313.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 270240721 + 42902500 = 16439^2 + 6550^2 .

It is an emirp because it is prime and its reverse (122341313) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 313143221 - 2² = 313143217 is a prime.

Together with 313143223, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 313143193 and 313143202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (313143223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 156571610 + 156571611.

It is an arithmetic number, because the mean of its divisors is an integer number (156571611).

Almost surely, 2^313143221 is an apocalyptic number.

It is an amenable number.

313143221 is a deficient number, since it is larger than the sum of its proper divisors (1).

313143221 is an equidigital number, since it uses as much as digits as its factorization.

313143221 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 313143221 is about 17695.8532148071. The cubic root of 313143221 is about 679.0696771800.

Adding to 313143221 its reverse (122341313), we get a palindrome (435484534).

The spelling of 313143221 in words is "three hundred thirteen million, one hundred forty-three thousand, two hundred twenty-one".