20638848 has 64 divisors (see below), whose sum is σ = 55667520. Its totient is φ = 6773760.

The previous prime is 20638819. The next prime is 20638853. The reversal of 20638848 is 84883602.

It is a Cunningham number, because it is equal to 4543²-1.

It is a tau number, because it is divible by the number of its divisors (64).

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 26886 + ... + 27642.

It is an arithmetic number, because the mean of its divisors is an integer number (869805).

Almost surely, 2^20638848 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 20638848, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27833760).

20638848 is an abundant number, since it is smaller than the sum of its proper divisors (35028672).

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

20638848 is an equidigital number, since it uses as much as digits as its factorization.

20638848 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 845 (or 833 counting only the distinct ones).

The product of its (nonzero) digits is 73728, while the sum is 39.

The square root of 20638848 is about 4542.9998899406. Note that the first 3 decimals coincide. The cubic root of 20638848 is about 274.3016905377.

The spelling of 20638848 in words is "twenty million, six hundred thirty-eight thousand, eight hundred forty-eight".