22221636 has 12 divisors (see below), whose sum is σ = 51850512. Its totient is φ = 7407208.

The previous prime is 22221599. The next prime is 22221649. The reversal of 22221636 is 63612222.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×22221636² = 987602213032992, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

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, 925890 + ... + 925913.

It is an arithmetic number, because the mean of its divisors is an integer number (4320876).

Almost surely, 2^22221636 is an apocalyptic number.

It is an amenable number.

22221636 is an abundant number, since it is smaller than the sum of its proper divisors (29628876).

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

22221636 is a wasteful number, since it uses less digits than its factorization.

22221636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1851810 (or 1851808 counting only the distinct ones).

The product of its digits is 1728, while the sum is 24.

The square root of 22221636 is about 4713.9830292440. The cubic root of 22221636 is about 281.1417495507.

Adding to 22221636 its reverse (63612222), we get a palindrome (85833858).

The spelling of 22221636 in words is "twenty-two million, two hundred twenty-one thousand, six hundred thirty-six".