18193917840 has 240 divisors, whose sum is σ = 65044920192. Its totient is φ = 4121100288.

The previous prime is 18193917817. The next prime is 18193917853. The reversal of 18193917840 is 4871939181.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (240).

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, 31531632 + ... + 31532208.

Almost surely, 2^18193917840 is an apocalyptic number.

18193917840 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 18193917840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32522460096).

18193917840 is an abundant number, since it is smaller than the sum of its proper divisors (46851002352).

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

18193917840 is a wasteful number, since it uses less digits than its factorization.

18193917840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 874 (or 731 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 51.

The spelling of 18193917840 in words is "eighteen billion, one hundred ninety-three million, nine hundred seventeen thousand, eight hundred forty".