20748 has 48 divisors (see below), whose sum is σ = 62720. Its totient is φ = 5184.

The previous prime is 20747. The next prime is 20749. The reversal of 20748 is 84702.

It is a happy number.

20748 is nontrivially palindromic in base 9.

It is an interprime number because it is at equal distance from previous prime (20747) and next prime (20749).

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (20743) by changing a digit.

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 in 15 ways as a sum of consecutive naturals, for example, 1083 + ... + 1101.

2²⁰⁷⁴⁸ is an apocalyptic number.

20748 is a gapful number since it is divisible by the number (28) 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 20748, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31360).

20748 is an abundant number, since it is smaller than the sum of its proper divisors (41972).

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

20748 is a wasteful number, since it uses less digits than its factorization.

20748 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46 (or 44 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 21.

The square root of 20748 is about 144.0416606402. The cubic root of 20748 is about 27.4784404023.

The spelling of 20748 in words is "twenty thousand, seven hundred forty-eight".