18985567 has 2 divisors, whose sum is σ = 18985568. Its totient is φ = 18985566.

The previous prime is 18985559. The next prime is 18985573. The reversal of 18985567 is 76558981.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18985567 - 2³ = 18985559 is a prime.

It is a super-2 number, since 2×18985567² = 720903508622978, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 18985567.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18985537) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9492783 + 9492784.

It is an arithmetic number, because the mean of its divisors is an integer number (9492784).

Almost surely, 2^18985567 is an apocalyptic number.

18985567 is a deficient number, since it is larger than the sum of its proper divisors (1).

18985567 is an equidigital number, since it uses as much as digits as its factorization.

18985567 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 604800, while the sum is 49.

The square root of 18985567 is about 4357.2430503703. The cubic root of 18985567 is about 266.7725810178.

The spelling of 18985567 in words is "eighteen million, nine hundred eighty-five thousand, five hundred sixty-seven".