18046821599 has 4 divisors (see below), whose sum is σ = 18059722800. Its totient is φ = 18033920400.

The previous prime is 18046821589. The next prime is 18046821643. The reversal of 18046821599 is 99512864081.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99512864081 = 433 ⋅229821857.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18046821599 is a prime.

It is a super-2 number, since 2×18046821599² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18046821599.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18046821589) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6448502 + ... + 6451299.

It is an arithmetic number, because the mean of its divisors is an integer number (4514930700).

Almost surely, 2^18046821599 is an apocalyptic number.

18046821599 is a deficient number, since it is larger than the sum of its proper divisors (12901201).

18046821599 is a wasteful number, since it uses less digits than its factorization.

18046821599 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12901200.

The product of its (nonzero) digits is 1244160, while the sum is 53.

The spelling of 18046821599 in words is "eighteen billion, forty-six million, eight hundred twenty-one thousand, five hundred ninety-nine".