22131220 has 24 divisors (see below), whose sum is σ = 46577664. Its totient is φ = 8833056.

The previous prime is 22131211. The next prime is 22131223. The reversal of 22131220 is 2213122.

It is a self number, because there is not a number n which added to its sum of digits gives 22131220.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22131223) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11229 + ... + 13051.

It is an arithmetic number, because the mean of its divisors is an integer number (1940736).

Almost surely, 2^22131220 is an apocalyptic number.

22131220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

22131220 is an abundant number, since it is smaller than the sum of its proper divisors (24446444).

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

22131220 is a wasteful number, since it uses less digits than its factorization.

22131220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2439 (or 2437 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 22131220 is about 4704.3830626342. The cubic root of 22131220 is about 280.7599254775.

Adding to 22131220 its reverse (2213122), we get a palindrome (24344342).

The spelling of 22131220 in words is "twenty-two million, one hundred thirty-one thousand, two hundred twenty".