22218840 has 128 divisors (see below), whose sum is σ = 84672000. Its totient is φ = 5076864.

The previous prime is 22218799. The next prime is 22218841. The reversal of 22218840 is 4881222.

22218840 = 487² + 488² + ... + 566².

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22218841) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6091 + ... + 9029.

It is an arithmetic number, because the mean of its divisors is an integer number (661500).

Almost surely, 2^22218840 is an apocalyptic number.

22218840 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 22218840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42336000).

22218840 is an abundant number, since it is smaller than the sum of its proper divisors (62453160).

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

22218840 is a wasteful number, since it uses less digits than its factorization.

22218840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2966 (or 2956 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 27.

The square root of 22218840 is about 4713.6864554189. The cubic root of 22218840 is about 281.1299576600.

The spelling of 22218840 in words is "twenty-two million, two hundred eighteen thousand, eight hundred forty".