20448864 has 144 divisors (see below), whose sum is σ = 63488880. Its totient is φ = 6220800.

The previous prime is 20448859. The next prime is 20448881. The reversal of 20448864 is 46884402.

It is a tau number, because it is divible by the number of its divisors (144).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 202414 + ... + 202514.

It is an arithmetic number, because the mean of its divisors is an integer number (440895).

Almost surely, 2^20448864 is an apocalyptic number.

20448864 is a gapful number since it is divisible by the number (24) 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 20448864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31744440).

20448864 is an abundant number, since it is smaller than the sum of its proper divisors (43040016).

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

20448864 is a wasteful number, since it uses less digits than its factorization.

20448864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173 (or 162 counting only the distinct ones).

The product of its (nonzero) digits is 49152, while the sum is 36.

The square root of 20448864 is about 4522.0420166115. The cubic root of 20448864 is about 273.4574305951.

It can be divided in two parts, 20448 and 864, that added together give a palindrome (21312).

The spelling of 20448864 in words is "twenty million, four hundred forty-eight thousand, eight hundred sixty-four".