18331253987 has 2 divisors, whose sum is σ = 18331253988. Its totient is φ = 18331253986.

The previous prime is 18331253981. The next prime is 18331254013. The reversal of 18331253987 is 78935213381.

It is a weak prime.

It is an emirp because it is prime and its reverse (78935213381) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18331253987 - 2¹⁰ = 18331252963 is a prime.

It is not a weakly prime, because it can be changed into another prime (18331253981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9165626993 + 9165626994.

It is an arithmetic number, because the mean of its divisors is an integer number (9165626994).

Almost surely, 2^18331253987 is an apocalyptic number.

18331253987 is a deficient number, since it is larger than the sum of its proper divisors (1).

18331253987 is an equidigital number, since it uses as much as digits as its factorization.

18331253987 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1088640, while the sum is 50.

The spelling of 18331253987 in words is "eighteen billion, three hundred thirty-one million, two hundred fifty-three thousand, nine hundred eighty-seven".