22212640 has 24 divisors (see below), whose sum is σ = 52477740. Its totient is φ = 8884992.

The previous prime is 22212629. The next prime is 22212649. The reversal of 22212640 is 4621222.

It can be written as a sum of positive squares in 2 ways, for example, as 21641104 + 571536 = 4652^2 + 756^2 .

It is not an unprimeable number, because it can be changed into a prime (22212649) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 69255 + ... + 69574.

Almost surely, 2^22212640 is an apocalyptic number.

22212640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

22212640 is an abundant number, since it is smaller than the sum of its proper divisors (30265100).

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

22212640 is a wasteful number, since it uses less digits than its factorization.

22212640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138844 (or 138836 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 19.

The square root of 22212640 is about 4713.0287501775. The cubic root of 22212640 is about 281.1038061615.

Adding to 22212640 its reverse (4621222), we get a palindrome (26833862).

The spelling of 22212640 in words is "twenty-two million, two hundred twelve thousand, six hundred forty".