31223120987 has 2 divisors, whose sum is σ = 31223120988. Its totient is φ = 31223120986.

The previous prime is 31223120923. The next prime is 31223121001. The reversal of 31223120987 is 78902132213.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (78902132213) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31223120987 - 2⁶ = 31223120923 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31223120987.

It is not a weakly prime, because it can be changed into another prime (31223170987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15611560493 + 15611560494.

It is an arithmetic number, because the mean of its divisors is an integer number (15611560494).

Almost surely, 2^31223120987 is an apocalyptic number.

31223120987 is a deficient number, since it is larger than the sum of its proper divisors (1).

31223120987 is an equidigital number, since it uses as much as digits as its factorization.

31223120987 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36288, while the sum is 38.

The spelling of 31223120987 in words is "thirty-one billion, two hundred twenty-three million, one hundred twenty thousand, nine hundred eighty-seven".