16659820800 has 540 divisors, whose sum is σ = 70414132096. Its totient is φ = 3807129600.

The previous prime is 16659820783. The next prime is 16659820823. The reversal of 16659820800 is 802895661.

It is a tau number, because it is divible by the number of its divisors (540).

It is a super-2 number, since 2×16659820800² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 3626505 + ... + 3631095.

Almost surely, 2^16659820800 is an apocalyptic number.

16659820800 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 16659820800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35207066048).

16659820800 is an abundant number, since it is smaller than the sum of its proper divisors (53754311296).

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

16659820800 is an equidigital number, since it uses as much as digits as its factorization.

16659820800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4636 (or 4608 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 45.

The spelling of 16659820800 in words is "sixteen billion, six hundred fifty-nine million, eight hundred twenty thousand, eight hundred".