313279781 has 2 divisors, whose sum is σ = 313279782. Its totient is φ = 313279780.

The previous prime is 313279763. The next prime is 313279783. The reversal of 313279781 is 187972313.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 252969025 + 60310756 = 15905^2 + 7766^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-313279781 is a prime.

It is a super-2 number, since 2×313279781² = 196288442366815922, which contains 22 as substring.

Together with 313279783, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (313279783) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 156639890 + 156639891.

It is an arithmetic number, because the mean of its divisors is an integer number (156639891).

Almost surely, 2^313279781 is an apocalyptic number.

It is an amenable number.

313279781 is a deficient number, since it is larger than the sum of its proper divisors (1).

313279781 is an equidigital number, since it uses as much as digits as its factorization.

313279781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 63504, while the sum is 41.

The square root of 313279781 is about 17699.7113253296. The cubic root of 313279781 is about 679.1683756582.

The spelling of 313279781 in words is "three hundred thirteen million, two hundred seventy-nine thousand, seven hundred eighty-one".