18609443 has 2 divisors, whose sum is σ = 18609444. Its totient is φ = 18609442.

The previous prime is 18609439. The next prime is 18609457. The reversal of 18609443 is 34490681.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18609443 - 2² = 18609439 is a prime.

It is a super-3 number, since 3×18609443³ (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (18609433) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9304721 + 9304722.

It is an arithmetic number, because the mean of its divisors is an integer number (9304722).

Almost surely, 2^18609443 is an apocalyptic number.

18609443 is a deficient number, since it is larger than the sum of its proper divisors (1).

18609443 is an equidigital number, since it uses as much as digits as its factorization.

18609443 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20736, while the sum is 35.

The square root of 18609443 is about 4313.8663632523. The cubic root of 18609443 is about 264.9991361073. Note that the first 3 decimals are identical.

The spelling of 18609443 in words is "eighteen million, six hundred nine thousand, four hundred forty-three".