22004640 has 288 divisors, whose sum is σ = 89631360. Its totient is φ = 4810752.

The previous prime is 22004639. The next prime is 22004683. The reversal of 22004640 is 4640022.

22004640 is a `hidden beast` number, since 2 + 20 + 0 + 4 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 372931 + ... + 372989.

It is an arithmetic number, because the mean of its divisors is an integer number (311220).

Almost surely, 2^22004640 is an apocalyptic number.

22004640 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 22004640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44815680).

22004640 is an abundant number, since it is smaller than the sum of its proper divisors (67626720).

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

22004640 is a wasteful number, since it uses less digits than its factorization.

22004640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 124 (or 113 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 22004640 is about 4690.9103594079. The cubic root of 22004640 is about 280.2236308664.

Adding to 22004640 its reverse (4640022), we get a palindrome (26644662).

The spelling of 22004640 in words is "twenty-two million, four thousand, six hundred forty".