18982391 has 2 divisors, whose sum is σ = 18982392. Its totient is φ = 18982390.

The previous prime is 18982339. The next prime is 18982417. The reversal of 18982391 is 19328981.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18982391 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18982331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9491195 + 9491196.

It is an arithmetic number, because the mean of its divisors is an integer number (9491196).

Almost surely, 2^18982391 is an apocalyptic number.

18982391 is a deficient number, since it is larger than the sum of its proper divisors (1).

18982391 is an equidigital number, since it uses as much as digits as its factorization.

18982391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 31104, while the sum is 41.

The square root of 18982391 is about 4356.8785844914. The cubic root of 18982391 is about 266.7577045072.

The spelling of 18982391 in words is "eighteen million, nine hundred eighty-two thousand, three hundred ninety-one".