22118640 has 80 divisors (see below), whose sum is σ = 71566848. Its totient is φ = 5640448.

The previous prime is 22118609. The next prime is 22118647. The reversal of 22118640 is 4681122.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 22118640.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22118647) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3517 + ... + 7523.

Almost surely, 2^22118640 is an apocalyptic number.

22118640 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 22118640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35783424).

22118640 is an abundant number, since it is smaller than the sum of its proper divisors (49448208).

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

22118640 is a wasteful number, since it uses less digits than its factorization.

22118640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4046 (or 4040 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 24.

The square root of 22118640 is about 4703.0458215926. The cubic root of 22118640 is about 280.7067181487.

Adding to 22118640 its reverse (4681122), we get a palindrome (26799762).

The spelling of 22118640 in words is "twenty-two million, one hundred eighteen thousand, six hundred forty".