31313121197 has 2 divisors, whose sum is σ = 31313121198. Its totient is φ = 31313121196.

The previous prime is 31313121193. The next prime is 31313121239. The reversal of 31313121197 is 79112131313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 30769018921 + 544102276 = 175411^2 + 23326^2 .

It is an emirp because it is prime and its reverse (79112131313) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31313121197 - 2² = 31313121193 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31313121193) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15656560598 + 15656560599.

It is an arithmetic number, because the mean of its divisors is an integer number (15656560599).

Almost surely, 2^31313121197 is an apocalyptic number.

It is an amenable number.

31313121197 is a deficient number, since it is larger than the sum of its proper divisors (1).

31313121197 is an equidigital number, since it uses as much as digits as its factorization.

31313121197 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3402, while the sum is 32.

The spelling of 31313121197 in words is "thirty-one billion, three hundred thirteen million, one hundred twenty-one thousand, one hundred ninety-seven".