18311983 has 2 divisors, whose sum is σ = 18311984. Its totient is φ = 18311982.

The previous prime is 18311957. The next prime is 18311987. The reversal of 18311983 is 38911381.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18311983 - 2⁹ = 18311471 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18311987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9155991 + 9155992.

It is an arithmetic number, because the mean of its divisors is an integer number (9155992).

Almost surely, 2^18311983 is an apocalyptic number.

18311983 is a deficient number, since it is larger than the sum of its proper divisors (1).

18311983 is an equidigital number, since it uses as much as digits as its factorization.

18311983 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5184, while the sum is 34.

The square root of 18311983 is about 4279.2502848046. The cubic root of 18311983 is about 263.5795985340.

The spelling of 18311983 in words is "eighteen million, three hundred eleven thousand, nine hundred eighty-three".