23840 has 24 divisors (see below), whose sum is σ = 56700. Its totient is φ = 9472.

The previous prime is 23833. The next prime is 23857. The reversal of 23840 is 4832.

It can be written as a sum of positive squares in 2 ways, for example, as 21904 + 1936 = 148^2 + 44^2 .

It is an unprimeable number.

23840 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 86 + ... + 234.

2²³⁸⁴⁰ is an apocalyptic number.

23840 is a gapful number since it is divisible by the number (20) 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 23840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28350).

23840 is an abundant number, since it is smaller than the sum of its proper divisors (32860).

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

23840 is a wasteful number, since it uses less digits than its factorization.

23840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164 (or 156 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 23840 is about 154.4020725250. The cubic root of 23840 is about 28.7807484509.

The spelling of 23840 in words is "twenty-three thousand, eight hundred forty".