18809443 has 2 divisors, whose sum is σ = 18809444. Its totient is φ = 18809442.

The previous prime is 18809419. The next prime is 18809471. The reversal of 18809443 is 34490881.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18809443 is a prime.

It is not a weakly prime, because it can be changed into another prime (18809473) 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, 9404721 + 9404722.

It is an arithmetic number, because the mean of its divisors is an integer number (9404722).

Almost surely, 2^18809443 is an apocalyptic number.

18809443 is a deficient number, since it is larger than the sum of its proper divisors (1).

18809443 is an equidigital number, since it uses as much as digits as its factorization.

18809443 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27648, while the sum is 37.

The square root of 18809443 is about 4336.9854738055. The cubic root of 18809443 is about 265.9450910839.

The spelling of 18809443 in words is "eighteen million, eight hundred nine thousand, four hundred forty-three".