22215640 has 16 divisors (see below), whose sum is σ = 49985280. Its totient is φ = 8886240.

The previous prime is 22215629. The next prime is 22215667. The reversal of 22215640 is 4651222.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 277656 + ... + 277735.

It is an arithmetic number, because the mean of its divisors is an integer number (3124080).

Almost surely, 2^22215640 is an apocalyptic number.

22215640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

22215640 is an abundant number, since it is smaller than the sum of its proper divisors (27769640).

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

22215640 is a wasteful number, since it uses less digits than its factorization.

22215640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 555402 (or 555398 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 22.

The square root of 22215640 is about 4713.3470061094. The cubic root of 22215640 is about 281.1164607200.

Adding to 22215640 its reverse (4651222), we get a palindrome (26866862).

The spelling of 22215640 in words is "twenty-two million, two hundred fifteen thousand, six hundred forty".