18991283 has 2 divisors, whose sum is σ = 18991284. Its totient is φ = 18991282.

The previous prime is 18991267. The next prime is 18991303. The reversal of 18991283 is 38219981.

It is a weak prime.

It is an emirp because it is prime and its reverse (38219981) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18991283 - 2⁴ = 18991267 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18991283.

It is not a weakly prime, because it can be changed into another prime (18991213) 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, 9495641 + 9495642.

It is an arithmetic number, because the mean of its divisors is an integer number (9495642).

Almost surely, 2^18991283 is an apocalyptic number.

18991283 is a deficient number, since it is larger than the sum of its proper divisors (1).

18991283 is an equidigital number, since it uses as much as digits as its factorization.

18991283 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 31104, while the sum is 41.

The square root of 18991283 is about 4357.8989203514. The cubic root of 18991283 is about 266.7993508103.

The spelling of 18991283 in words is "eighteen million, nine hundred ninety-one thousand, two hundred eighty-three".