18098781559 has 4 divisors (see below), whose sum is σ = 18099140416. Its totient is φ = 18098422704.

The previous prime is 18098781551. The next prime is 18098781601. The reversal of 18098781559 is 95518789081.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18098781559 - 2³ = 18098781551 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18098781497 and 18098781506.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18098781551) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 88374 + ... + 209779.

It is an arithmetic number, because the mean of its divisors is an integer number (4524785104).

Almost surely, 2^18098781559 is an apocalyptic number.

18098781559 is a deficient number, since it is larger than the sum of its proper divisors (358857).

18098781559 is an equidigital number, since it uses as much as digits as its factorization.

18098781559 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 358856.

The product of its (nonzero) digits is 7257600, while the sum is 61.

The spelling of 18098781559 in words is "eighteen billion, ninety-eight million, seven hundred eighty-one thousand, five hundred fifty-nine".