20889856 has 36 divisors (see below), whose sum is σ = 44912812. Its totient is φ = 9639936.

The previous prime is 20889839. The next prime is 20889857. The reversal of 20889856 is 65898802.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 12960000 + 7929856 = 3600^2 + 2816^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20889857) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 190 + ... + 6466.

Almost surely, 2^20889856 is an apocalyptic number.

20889856 is a gapful number since it is divisible by the number (26) 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 20889856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22456406).

20889856 is an abundant number, since it is smaller than the sum of its proper divisors (24022956).

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

20889856 is an equidigital number, since it uses as much as digits as its factorization.

20889856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6306 (or 6292 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 46.

The square root of 20889856 is about 4570.5421997833. The cubic root of 20889856 is about 275.4092243447.

The spelling of 20889856 in words is "twenty million, eight hundred eighty-nine thousand, eight hundred fifty-six".