20499916800 has 432 divisors, whose sum is σ = 74558352960. Its totient is φ = 4965171200.

The previous prime is 20499916771. The next prime is 20499916819. The reversal of 20499916800 is 861999402.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 20499916800.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 18585049 + ... + 18586151.

It is an arithmetic number, because the mean of its divisors is an integer number (172588780).

Almost surely, 2^20499916800 is an apocalyptic number.

20499916800 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 20499916800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37279176480).

20499916800 is an abundant number, since it is smaller than the sum of its proper divisors (54058436160).

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

20499916800 is a wasteful number, since it uses less digits than its factorization.

20499916800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1160 (or 1124 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 48.

The spelling of 20499916800 in words is "twenty billion, four hundred ninety-nine million, nine hundred sixteen thousand, eight hundred".