18000947 has 2 divisors, whose sum is σ = 18000948. Its totient is φ = 18000946.

The previous prime is 18000937. The next prime is 18000949. The reversal of 18000947 is 74900081.

It is a strong prime.

It is an emirp because it is prime and its reverse (74900081) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18000947 - 2⁶ = 18000883 is a prime.

Together with 18000949, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (18000949) 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, 9000473 + 9000474.

It is an arithmetic number, because the mean of its divisors is an integer number (9000474).

Almost surely, 2^18000947 is an apocalyptic number.

18000947 is a deficient number, since it is larger than the sum of its proper divisors (1).

18000947 is an equidigital number, since it uses as much as digits as its factorization.

18000947 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2016, while the sum is 29.

The square root of 18000947 is about 4242.7522906717. The cubic root of 18000947 is about 262.0787353442.

The spelling of 18000947 in words is "eighteen million, nine hundred forty-seven", and thus it is an aban number.