19181085800 has 96 divisors (see below), whose sum is σ = 45412253400. Its totient is φ = 7532974080.

The previous prime is 19181085761. The next prime is 19181085811. The reversal of 19181085800 is 858018191.

It is a happy number.

It can be written as a sum of positive squares in 12 ways, for example, as 748679044 + 18432406756 = 27362^2 + 135766^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3340532 + ... + 3346268.

Almost surely, 2^19181085800 is an apocalyptic number.

19181085800 is a gapful number since it is divisible by the number (10) 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 19181085800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22706126700).

19181085800 is an abundant number, since it is smaller than the sum of its proper divisors (26231167600).

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

19181085800 is a wasteful number, since it uses less digits than its factorization.

19181085800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6055 (or 6046 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 41.

The spelling of 19181085800 in words is "nineteen billion, one hundred eighty-one million, eighty-five thousand, eight hundred".