18180198400 has 312 divisors, whose sum is σ = 55513224704. Its totient is φ = 5750784000.

The previous prime is 18180198389. The next prime is 18180198401. The reversal of 18180198400 is 489108181.

It is a super-2 number, since 2×18180198400² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18180198401) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9317425 + ... + 9319375.

Almost surely, 2^18180198400 is an apocalyptic number.

18180198400 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 18180198400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27756612352).

18180198400 is an abundant number, since it is smaller than the sum of its proper divisors (37333026304).

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

18180198400 is a wasteful number, since it uses less digits than its factorization.

18180198400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2005 (or 1978 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 40.

The spelling of 18180198400 in words is "eighteen billion, one hundred eighty million, one hundred ninety-eight thousand, four hundred".