19498187808 has 864 divisors, whose sum is σ = 71149373568. Its totient is φ = 5218836480.

The previous prime is 19498187783. The next prime is 19498187857. The reversal of 19498187808 is 80878189491.

It is a tau number, because it is divible by the number of its divisors (864).

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 367890310 + ... + 367890362.

It is an arithmetic number, because the mean of its divisors is an integer number (82348812).

Almost surely, 2^19498187808 is an apocalyptic number.

19498187808 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19498187808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35574686784).

19498187808 is an abundant number, since it is smaller than the sum of its proper divisors (51651185760).

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

19498187808 is a wasteful number, since it uses less digits than its factorization.

19498187808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140 (or 109 counting only the distinct ones).

The product of its (nonzero) digits is 9289728, while the sum is 63.

The spelling of 19498187808 in words is "nineteen billion, four hundred ninety-eight million, one hundred eighty-seven thousand, eight hundred eight".