24640 has 56 divisors (see below), whose sum is σ = 73152. Its totient is φ = 7680.

The previous prime is 24631. The next prime is 24659. The reversal of 24640 is 4642.

It is a tau number, because it is divible by the number of its divisors (56).

It is a hoax number, since the sum of its digits (16) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (3) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2235 + ... + 2245.

2²⁴⁶⁴⁰ is an apocalyptic number.

24640 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 24640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36576).

24640 is an abundant number, since it is smaller than the sum of its proper divisors (48512).

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

24640 is a wasteful number, since it uses less digits than its factorization.

24640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35 (or 25 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 24640 is about 156.9713349628. The cubic root of 24640 is about 29.0991453952.

24640 divided by its sum of digits (16) gives a triangular number (1540 = T₅₅).

The spelling of 24640 in words is "twenty-four thousand, six hundred forty".