199806566400 has 1440 divisors, whose sum is σ = 877631328000. Its totient is φ = 43599790080.

The previous prime is 199806566363. The next prime is 199806566417. The reversal of 199806566400 is 4665608991.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (1440).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 2245017556 + ... + 2245017644.

It is an arithmetic number, because the mean of its divisors is an integer number (609466200).

Almost surely, 2^199806566400 is an apocalyptic number.

199806566400 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 199806566400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (438815664000).

199806566400 is an abundant number, since it is smaller than the sum of its proper divisors (677824761600).

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

199806566400 is an equidigital number, since it uses as much as digits as its factorization.

199806566400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172 (or 135 counting only the distinct ones).

The product of its (nonzero) digits is 2799360, while the sum is 54.

The spelling of 199806566400 in words is "one hundred ninety-nine billion, eight hundred six million, five hundred sixty-six thousand, four hundred".