18487559 has 2 divisors, whose sum is σ = 18487560. Its totient is φ = 18487558.

The previous prime is 18487543. The next prime is 18487583. The reversal of 18487559 is 95578481.

It is a weak prime.

It is an emirp because it is prime and its reverse (95578481) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18487559 - 2⁴ = 18487543 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18487519) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9243779 + 9243780.

It is an arithmetic number, because the mean of its divisors is an integer number (9243780).

Almost surely, 2^18487559 is an apocalyptic number.

18487559 is a deficient number, since it is larger than the sum of its proper divisors (1).

18487559 is an equidigital number, since it uses as much as digits as its factorization.

18487559 is an evil number, because the sum of its binary digits is even.

The product of its digits is 403200, while the sum is 47.

The square root of 18487559 is about 4299.7161534222. The cubic root of 18487559 is about 264.4193242399.

The spelling of 18487559 in words is "eighteen million, four hundred eighty-seven thousand, five hundred fifty-nine".