18266563 has 12 divisors (see below), whose sum is σ = 21443400. Its totient is φ = 15513792.

The previous prime is 18266561. The next prime is 18266569. The reversal of 18266563 is 36566281.

It is not a de Polignac number, because 18266563 - 2¹ = 18266561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18266561) 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 in 11 ways as a sum of consecutive naturals, for example, 3888 + ... + 7186.

It is an arithmetic number, because the mean of its divisors is an integer number (1786950).

Almost surely, 2^18266563 is an apocalyptic number.

18266563 is a deficient number, since it is larger than the sum of its proper divisors (3176837).

18266563 is a wasteful number, since it uses less digits than its factorization.

18266563 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3426 (or 3419 counting only the distinct ones).

The product of its digits is 51840, while the sum is 37.

The square root of 18266563 is about 4273.9399855403. The cubic root of 18266563 is about 263.3614955015.

The spelling of 18266563 in words is "eighteen million, two hundred sixty-six thousand, five hundred sixty-three".