22840 has 16 divisors (see below), whose sum is σ = 51480. Its totient is φ = 9120.

The previous prime is 22817. The next prime is 22853. The reversal of 22840 is 4822.

22840 = 30² + 31² + ... + 45².

It is a congruent number.

It is an unprimeable number.

22840 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 (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 246 + ... + 325.

2²²⁸⁴⁰ is an apocalyptic number.

22840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

22840 is an abundant number, since it is smaller than the sum of its proper divisors (28640).

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

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25740).

22840 is a wasteful number, since it uses less digits than its factorization.

22840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 582 (or 578 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

The square root of 22840 is about 151.1290838985. The cubic root of 22840 is about 28.3725715479.

The spelling of 22840 in words is "twenty-two thousand, eight hundred forty".