18203794440 has 192 divisors, whose sum is σ = 59695185600. Its totient is φ = 4438526976.

The previous prime is 18203794439. The next prime is 18203794457. The reversal of 18203794440 is 4449730281.

It is a junction number, because it is equal to n+sod(n) for n = 18203794392 and 18203794401.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2165766 + ... + 2174154.

It is an arithmetic number, because the mean of its divisors is an integer number (310912425).

Almost surely, 2^18203794440 is an apocalyptic number.

18203794440 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 18203794440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29847592800).

18203794440 is an abundant number, since it is smaller than the sum of its proper divisors (41491391160).

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

18203794440 is a wasteful number, since it uses less digits than its factorization.

18203794440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8536 (or 8519 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 42.

The spelling of 18203794440 in words is "eighteen billion, two hundred three million, seven hundred ninety-four thousand, four hundred forty".