31012121873 has 2 divisors, whose sum is σ = 31012121874. Its totient is φ = 31012121872.

The previous prime is 31012121857. The next prime is 31012121893. The reversal of 31012121873 is 37812121013.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29112208129 + 1899913744 = 170623^2 + 43588^2 .

It is a cyclic number.

It is not a de Polignac number, because 31012121873 - 2⁴ = 31012121857 is a prime.

It is not a weakly prime, because it can be changed into another prime (31012121893) 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, 15506060936 + 15506060937.

It is an arithmetic number, because the mean of its divisors is an integer number (15506060937).

Almost surely, 2^31012121873 is an apocalyptic number.

It is an amenable number.

31012121873 is a deficient number, since it is larger than the sum of its proper divisors (1).

31012121873 is an equidigital number, since it uses as much as digits as its factorization.

31012121873 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2016, while the sum is 29.

Adding to 31012121873 its reverse (37812121013), we get a palindrome (68824242886).

The spelling of 31012121873 in words is "thirty-one billion, twelve million, one hundred twenty-one thousand, eight hundred seventy-three".