18255563 has 2 divisors, whose sum is σ = 18255564. Its totient is φ = 18255562.

The previous prime is 18255553. The next prime is 18255577. The reversal of 18255563 is 36555281.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18255563 - 2⁴ = 18255547 is a prime.

It is equal to p_1166588 and since 18255563 and 1166588 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (18255533) 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, 9127781 + 9127782.

It is an arithmetic number, because the mean of its divisors is an integer number (9127782).

Almost surely, 2^18255563 is an apocalyptic number.

18255563 is a deficient number, since it is larger than the sum of its proper divisors (1).

18255563 is an equidigital number, since it uses as much as digits as its factorization.

18255563 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36000, while the sum is 35.

The square root of 18255563 is about 4272.6529229508. The cubic root of 18255563 is about 263.3086200526.

The spelling of 18255563 in words is "eighteen million, two hundred fifty-five thousand, five hundred sixty-three".