31211213207 has 2 divisors, whose sum is σ = 31211213208. Its totient is φ = 31211213206.

The previous prime is 31211213203. The next prime is 31211213237. The reversal of 31211213207 is 70231211213.

It is a weak prime.

It is an emirp because it is prime and its reverse (70231211213) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31211213207 - 2² = 31211213203 is a prime.

It is a super-2 number, since 2×31211213207² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31211213203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15605606603 + 15605606604.

It is an arithmetic number, because the mean of its divisors is an integer number (15605606604).

Almost surely, 2^31211213207 is an apocalyptic number.

31211213207 is a deficient number, since it is larger than the sum of its proper divisors (1).

31211213207 is an equidigital number, since it uses as much as digits as its factorization.

31211213207 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 504, while the sum is 23.

The spelling of 31211213207 in words is "thirty-one billion, two hundred eleven million, two hundred thirteen thousand, two hundred seven".