18398081505 has 16 divisors (see below), whose sum is σ = 29446389504. Its totient is φ = 9809157120.

The previous prime is 18398081503. The next prime is 18398081543. The reversal of 18398081505 is 50518089381.

It is not a de Polignac number, because 18398081505 - 2¹ = 18398081503 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18398081503) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 148441 + ... + 242550.

It is an arithmetic number, because the mean of its divisors is an integer number (1840399344).

Almost surely, 2^18398081505 is an apocalyptic number.

18398081505 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18398081505 is a deficient number, since it is larger than the sum of its proper divisors (11048307999).

18398081505 is a wasteful number, since it uses less digits than its factorization.

18398081505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 394136.

The product of its (nonzero) digits is 345600, while the sum is 48.

The spelling of 18398081505 in words is "eighteen billion, three hundred ninety-eight million, eighty-one thousand, five hundred five".