31100021231987 has 2 divisors, whose sum is σ = 31100021231988. Its totient is φ = 31100021231986.

The previous prime is 31100021231969. The next prime is 31100021232011. The reversal of 31100021231987 is 78913212000113.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31100021231987 - 2¹⁰ = 31100021230963 is a prime.

It is a super-2 number, since 2×31100021231987² (a number of 28 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 31100021231987.

It is not a weakly prime, because it can be changed into another prime (31100021233987) 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, 15550010615993 + 15550010615994.

It is an arithmetic number, because the mean of its divisors is an integer number (15550010615994).

Almost surely, 2^{31100021231987} is an apocalyptic number.

31100021231987 is a deficient number, since it is larger than the sum of its proper divisors (1).

31100021231987 is an equidigital number, since it uses as much as digits as its factorization.

31100021231987 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18144, while the sum is 38.

The spelling of 31100021231987 in words is "thirty-one trillion, one hundred billion, twenty-one million, two hundred thirty-one thousand, nine hundred eighty-seven".