22145440 has 48 divisors (see below), whose sum is σ = 53199720. Its totient is φ = 8709120.

The previous prime is 22145437. The next prime is 22145447. The reversal of 22145440 is 4454122.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 5400976 + 16744464 = 2324^2 + 4092^2 .

It is a zygodrome in base 3.

It is not an unprimeable number, because it can be changed into a prime (22145447) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 8626 + ... + 10894.

Almost surely, 2^22145440 is an apocalyptic number.

22145440 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 22145440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26599860).

22145440 is an abundant number, since it is smaller than the sum of its proper divisors (31054280).

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

22145440 is a wasteful number, since it uses less digits than its factorization.

22145440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2345 (or 2337 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 22.

The square root of 22145440 is about 4705.8941764557. The cubic root of 22145440 is about 280.8200449431.

Adding to 22145440 its reverse (4454122), we get a palindrome (26599562).

The spelling of 22145440 in words is "twenty-two million, one hundred forty-five thousand, four hundred forty".