313111021 has 2 divisors, whose sum is σ = 313111022. Its totient is φ = 313111020.

The previous prime is 313111003. The next prime is 313111031. The reversal of 313111021 is 120111313.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 244453225 + 68657796 = 15635^2 + 8286^2 .

It is a cyclic number.

It is not a de Polignac number, because 313111021 - 2¹¹ = 313108973 is a prime.

It is a super-2 number, since 2×313111021² = 196077022943324882, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 313110992 and 313111010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (313111031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 156555510 + 156555511.

It is an arithmetic number, because the mean of its divisors is an integer number (156555511).

Almost surely, 2^313111021 is an apocalyptic number.

It is an amenable number.

313111021 is a deficient number, since it is larger than the sum of its proper divisors (1).

313111021 is an equidigital number, since it uses as much as digits as its factorization.

313111021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18, while the sum is 13.

The square root of 313111021 is about 17694.9433737438. The cubic root of 313111021 is about 679.0464005112.

Adding to 313111021 its reverse (120111313), we get a palindrome (433222334).

The spelling of 313111021 in words is "three hundred thirteen million, one hundred eleven thousand, twenty-one".