20896 has 12 divisors (see below), whose sum is σ = 41202. Its totient is φ = 10432.

The previous prime is 20887. The next prime is 20897. The reversal of 20896 is 69802.

It can be written as a sum of positive squares in only one way, i.e., 19600 + 1296 = 140^2 + 36^2 .

It is a plaindrome in base 11 and base 14.

It is a self number, because there is not a number n which added to its sum of digits gives 20896.

It is not an unprimeable number, because it can be changed into a prime (20897) by changing a digit.

20896 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 295 + ... + 358.

2²⁰⁸⁹⁶ is an apocalyptic number.

It is an amenable number.

20896 is a deficient number, since it is larger than the sum of its proper divisors (20306).

20896 is an equidigital number, since it uses as much as digits as its factorization.

20896 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 663 (or 655 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 25.

The square root of 20896 is about 144.5544879967. The cubic root of 20896 is about 27.5436222272.

The spelling of 20896 in words is "twenty thousand, eight hundred ninety-six".