22306440 has 128 divisors (see below), whose sum is σ = 73382400. Its totient is φ = 5391360.

The previous prime is 22306439. The next prime is 22306463. The reversal of 22306440 is 4460322.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 123150 + ... + 123330.

It is an arithmetic number, because the mean of its divisors is an integer number (573300).

Almost surely, 2^22306440 is an apocalyptic number.

22306440 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 22306440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36691200).

22306440 is an abundant number, since it is smaller than the sum of its proper divisors (51075960).

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

22306440 is a wasteful number, since it uses less digits than its factorization.

22306440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 287 (or 283 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 21.

The square root of 22306440 is about 4722.9694049401. The cubic root of 22306440 is about 281.4989341714.

Adding to 22306440 its reverse (4460322), we get a palindrome (26766762).

The spelling of 22306440 in words is "twenty-two million, three hundred six thousand, four hundred forty".