18974491 has 2 divisors, whose sum is σ = 18974492. Its totient is φ = 18974490.

The previous prime is 18974489. The next prime is 18974507. The reversal of 18974491 is 19447981.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18974491 - 2¹ = 18974489 is a prime.

Together with 18974489, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (18974441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9487245 + 9487246.

It is an arithmetic number, because the mean of its divisors is an integer number (9487246).

Almost surely, 2^18974491 is an apocalyptic number.

18974491 is a deficient number, since it is larger than the sum of its proper divisors (1).

18974491 is an equidigital number, since it uses as much as digits as its factorization.

18974491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 72576, while the sum is 43.

The square root of 18974491 is about 4355.9718777788. The cubic root of 18974491 is about 266.7206933937.

The spelling of 18974491 in words is "eighteen million, nine hundred seventy-four thousand, four hundred ninety-one".