31311307843 has 2 divisors, whose sum is σ = 31311307844. Its totient is φ = 31311307842.

The previous prime is 31311307817. The next prime is 31311307861. The reversal of 31311307843 is 34870311313.

It is a strong prime.

It is an emirp because it is prime and its reverse (34870311313) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31311307843 - 2³³ = 22721373251 is a prime.

It is a super-2 number, since 2×31311307843² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 31311307799 and 31311307808.

It is not a weakly prime, because it can be changed into another prime (31311307043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15655653921 + 15655653922.

It is an arithmetic number, because the mean of its divisors is an integer number (15655653922).

Almost surely, 2^31311307843 is an apocalyptic number.

31311307843 is a deficient number, since it is larger than the sum of its proper divisors (1).

31311307843 is an equidigital number, since it uses as much as digits as its factorization.

31311307843 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18144, while the sum is 34.

The spelling of 31311307843 in words is "thirty-one billion, three hundred eleven million, three hundred seven thousand, eight hundred forty-three".