20669644800 has 900 divisors, whose sum is σ = 88494492240. Its totient is φ = 4671406080.

The previous prime is 20669644799. The next prime is 20669644829. The reversal of 20669644800 is 844696602.

20669644800 is a `hidden beast` number, since 20 + 66 + 96 + 4 + 480 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (900).

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 232243156 + ... + 232243244.

Almost surely, 2^20669644800 is an apocalyptic number.

20669644800 is a gapful number since it is divisible by the number (20) 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 20669644800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44247246120).

20669644800 is an abundant number, since it is smaller than the sum of its proper divisors (67824847440).

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

20669644800 is an frugal number, since it uses more digits than its factorization.

20669644800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146 (or 106 counting only the distinct ones).

The product of its (nonzero) digits is 497664, while the sum is 45.

The spelling of 20669644800 in words is "twenty billion, six hundred sixty-nine million, six hundred forty-four thousand, eight hundred".