31871867987 has 2 divisors, whose sum is σ = 31871867988. Its totient is φ = 31871867986.

The previous prime is 31871867983. The next prime is 31871868011. The reversal of 31871867987 is 78976817813.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31871867987 - 2² = 31871867983 is a prime.

It is not a weakly prime, because it can be changed into another prime (31871867981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15935933993 + 15935933994.

It is an arithmetic number, because the mean of its divisors is an integer number (15935933994).

Almost surely, 2^31871867987 is an apocalyptic number.

31871867987 is a deficient number, since it is larger than the sum of its proper divisors (1).

31871867987 is an equidigital number, since it uses as much as digits as its factorization.

31871867987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 28449792, while the sum is 65.

The spelling of 31871867987 in words is "thirty-one billion, eight hundred seventy-one million, eight hundred sixty-seven thousand, nine hundred eighty-seven".