18984947 has 2 divisors, whose sum is σ = 18984948. Its totient is φ = 18984946.

The previous prime is 18984943. The next prime is 18984949. The reversal of 18984947 is 74948981.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18984947 - 2² = 18984943 is a prime.

Together with 18984949, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 18984895 and 18984904.

It is not a weakly prime, because it can be changed into another prime (18984941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9492473 + 9492474.

It is an arithmetic number, because the mean of its divisors is an integer number (9492474).

Almost surely, 2^18984947 is an apocalyptic number.

18984947 is a deficient number, since it is larger than the sum of its proper divisors (1).

18984947 is an equidigital number, since it uses as much as digits as its factorization.

18984947 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 580608, while the sum is 50.

The square root of 18984947 is about 4357.1719038844. The cubic root of 18984947 is about 266.7696770434.

The spelling of 18984947 in words is "eighteen million, nine hundred eighty-four thousand, nine hundred forty-seven".