31103311118021 has 2 divisors, whose sum is σ = 31103311118022. Its totient is φ = 31103311118020.

The previous prime is 31103311117999. The next prime is 31103311118051. The reversal of 31103311118021 is 12081111330113.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24916719472225 + 6186591645796 = 4991665^2 + 2487286^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31103311118021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31103311118051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15551655559010 + 15551655559011.

It is an arithmetic number, because the mean of its divisors is an integer number (15551655559011).

Almost surely, 2^{31103311118021} is an apocalyptic number.

It is an amenable number.

31103311118021 is a deficient number, since it is larger than the sum of its proper divisors (1).

31103311118021 is an equidigital number, since it uses as much as digits as its factorization.

31103311118021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 26.

Adding to 31103311118021 its reverse (12081111330113), we get a palindrome (43184422448134).

The spelling of 31103311118021 in words is "thirty-one trillion, one hundred three billion, three hundred eleven million, one hundred eighteen thousand, twenty-one".