16638220800 has 480 divisors, whose sum is σ = 63080962560. Its totient is φ = 4290969600.

The previous prime is 16638220799. The next prime is 16638220801. The reversal of 16638220800 is 802283661.

16638220800 is a `hidden beast` number, since 16 + 638 + 2 + 2 + 0 + 8 + 0 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (16638220799) and next prime (16638220801).

It is a tau number, because it is divible by the number of its divisors (480).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (16638220801) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 10712824 + ... + 10714376.

It is an arithmetic number, because the mean of its divisors is an integer number (131418672).

Almost surely, 2^16638220800 is an apocalyptic number.

16638220800 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 16638220800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31540481280).

16638220800 is an abundant number, since it is smaller than the sum of its proper divisors (46442741760).

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

16638220800 is a wasteful number, since it uses less digits than its factorization.

16638220800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1621 (or 1594 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The spelling of 16638220800 in words is "sixteen billion, six hundred thirty-eight million, two hundred twenty thousand, eight hundred".