313997843821 has 2 divisors, whose sum is σ = 313997843822. Its totient is φ = 313997843820.

The previous prime is 313997843801. The next prime is 313997843849. The reversal of 313997843821 is 128348799313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 310438408900 + 3559434921 = 557170^2 + 59661^2 .

It is a cyclic number.

It is not a de Polignac number, because 313997843821 - 2⁹ = 313997843309 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (313997843801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 156998921910 + 156998921911.

It is an arithmetic number, because the mean of its divisors is an integer number (156998921911).

Almost surely, 2^313997843821 is an apocalyptic number.

It is an amenable number.

313997843821 is a deficient number, since it is larger than the sum of its proper divisors (1).

313997843821 is an equidigital number, since it uses as much as digits as its factorization.

313997843821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7838208, while the sum is 58.

The spelling of 313997843821 in words is "three hundred thirteen billion, nine hundred ninety-seven million, eight hundred forty-three thousand, eight hundred twenty-one".