20813648 has 40 divisors (see below), whose sum is σ = 43092480. Its totient is φ = 9717120.

The previous prime is 20813623. The next prime is 20813669. The reversal of 20813648 is 84631802.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13661 + ... + 15107.

It is an arithmetic number, because the mean of its divisors is an integer number (1077312).

Almost surely, 2^20813648 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 20813648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21546240).

20813648 is an abundant number, since it is smaller than the sum of its proper divisors (22278832).

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

20813648 is a wasteful number, since it uses less digits than its factorization.

20813648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1515 (or 1509 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 32.

The square root of 20813648 is about 4562.1977160136. The cubic root of 20813648 is about 275.0739107120.

The spelling of 20813648 in words is "twenty million, eight hundred thirteen thousand, six hundred forty-eight".