16855171998 has 48 divisors (see below), whose sum is σ = 39307507344. Its totient is φ = 4804289280.

The previous prime is 16855171973. The next prime is 16855172011. The reversal of 16855171998 is 89917155861.

It is a congruent number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 55686 + ... + 191862.

It is an arithmetic number, because the mean of its divisors is an integer number (818906403).

Almost surely, 2^16855171998 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 16855171998, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19653753672).

16855171998 is an abundant number, since it is smaller than the sum of its proper divisors (22452335346).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

16855171998 is a wasteful number, since it uses less digits than its factorization.

16855171998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136617 (or 136610 counting only the distinct ones).

The product of its digits is 5443200, while the sum is 60.

The spelling of 16855171998 in words is "sixteen billion, eight hundred fifty-five million, one hundred seventy-one thousand, nine hundred ninety-eight".