20808208644440 has 32 divisors (see below), whose sum is σ = 53506822229280. Its totient is φ = 7134242963712.

The previous prime is 20808208644407. The next prime is 20808208644449. The reversal of 20808208644440 is 4444680280802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20808208644449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 37157515157 + ... + 37157515716.

It is an arithmetic number, because the mean of its divisors is an integer number (1672088194665).

Almost surely, 2^{20808208644440} is an apocalyptic number.

20808208644440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20808208644440 is an abundant number, since it is smaller than the sum of its proper divisors (32698613584840).

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

20808208644440 is a wasteful number, since it uses less digits than its factorization.

20808208644440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74315030891 (or 74315030887 counting only the distinct ones).

The product of its (nonzero) digits is 3145728, while the sum is 50.

The spelling of 20808208644440 in words is "twenty trillion, eight hundred eight billion, two hundred eight million, six hundred forty-four thousand, four hundred forty".