22145550 has 144 divisors (see below), whose sum is σ = 67174272. Its totient is φ = 4804800.

The previous prime is 22145549. The next prime is 22145551. The reversal of 22145550 is 5554122.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (22145549) and next prime (22145551).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 22145550.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22145551) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 168985 + ... + 169115.

It is an arithmetic number, because the mean of its divisors is an integer number (466488).

Almost surely, 2^22145550 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 22145550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33587136).

22145550 is an abundant number, since it is smaller than the sum of its proper divisors (45028722).

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

22145550 is a wasteful number, since it uses less digits than its factorization.

22145550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 183 (or 171 counting only the distinct ones).

The product of its (nonzero) digits is 2000, while the sum is 24.

The square root of 22145550 is about 4705.9058639119. The cubic root of 22145550 is about 280.8205099020.

Adding to 22145550 its reverse (5554122), we get a palindrome (27699672).

The spelling of 22145550 in words is "twenty-two million, one hundred forty-five thousand, five hundred fifty".