20099808 has 72 divisors (see below), whose sum is σ = 57808296. Its totient is φ = 6624000.

The previous prime is 20099801. The next prime is 20099819. The reversal of 20099808 is 80899002.

It is a tau number, because it is divible by the number of its divisors (72).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20099801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 28743 + ... + 29433.

It is an arithmetic number, because the mean of its divisors is an integer number (802893).

Almost surely, 2^20099808 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20099808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28904148).

20099808 is an abundant number, since it is smaller than the sum of its proper divisors (37708488).

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

20099808 is a wasteful number, since it uses less digits than its factorization.

20099808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 808 (or 797 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 36.

The square root of 20099808 is about 4483.2809414535. The cubic root of 20099808 is about 271.8925469452.

The spelling of 20099808 in words is "twenty million, ninety-nine thousand, eight hundred eight".