31012139887 has 2 divisors, whose sum is σ = 31012139888. Its totient is φ = 31012139886.

The previous prime is 31012139843. The next prime is 31012139897. The reversal of 31012139887 is 78893121013.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31012139887 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31012139827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15506069943 + 15506069944.

It is an arithmetic number, because the mean of its divisors is an integer number (15506069944).

Almost surely, 2^31012139887 is an apocalyptic number.

31012139887 is a deficient number, since it is larger than the sum of its proper divisors (1).

31012139887 is an equidigital number, since it uses as much as digits as its factorization.

31012139887 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72576, while the sum is 43.

The spelling of 31012139887 in words is "thirty-one billion, twelve million, one hundred thirty-nine thousand, eight hundred eighty-seven".