22415540 has 72 divisors (see below), whose sum is σ = 55588680. Its totient is φ = 7569408.

The previous prime is 22415507. The next prime is 22415543. The reversal of 22415540 is 4551422.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 4892944 + 17522596 = 2212^2 + 4186^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22415543) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 87092 + ... + 87348.

It is an arithmetic number, because the mean of its divisors is an integer number (772065).

Almost surely, 2^22415540 is an apocalyptic number.

22415540 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 22415540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27794340).

22415540 is an abundant number, since it is smaller than the sum of its proper divisors (33173140).

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

22415540 is a wasteful number, since it uses less digits than its factorization.

22415540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 369 (or 360 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 23.

The square root of 22415540 is about 4734.5052539838. The cubic root of 22415540 is about 281.9571217271.

Adding to 22415540 its reverse (4551422), we get a palindrome (26966962).

The spelling of 22415540 in words is "twenty-two million, four hundred fifteen thousand, five hundred forty".