312123121987 has 2 divisors, whose sum is σ = 312123121988. Its totient is φ = 312123121986.

The previous prime is 312123121969. The next prime is 312123122053. The reversal of 312123121987 is 789121321213.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-312123121987 is a prime.

It is not a weakly prime, because it can be changed into another prime (312123121907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 156061560993 + 156061560994.

It is an arithmetic number, because the mean of its divisors is an integer number (156061560994).

Almost surely, 2^312123121987 is an apocalyptic number.

312123121987 is a deficient number, since it is larger than the sum of its proper divisors (1).

312123121987 is an equidigital number, since it uses as much as digits as its factorization.

312123121987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 36288, while the sum is 40.

The spelling of 312123121987 in words is "three hundred twelve billion, one hundred twenty-three million, one hundred twenty-one thousand, nine hundred eighty-seven".