21221132 has 12 divisors (see below), whose sum is σ = 37246440. Its totient is φ = 10579296.

The previous prime is 21221131. The next prime is 21221153. The reversal of 21221132 is 23112212.

It is a happy number.

It is a super-2 number, since 2×21221132² = 900672886722848, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21221131) 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, 6257 + ... + 9032.

It is an arithmetic number, because the mean of its divisors is an integer number (3103870).

Almost surely, 2^21221132 is an apocalyptic number.

It is an amenable number.

21221132 is a deficient number, since it is larger than the sum of its proper divisors (16025308).

21221132 is a wasteful number, since it uses less digits than its factorization.

21221132 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15640 (or 15638 counting only the distinct ones).

The product of its digits is 48, while the sum is 14.

The square root of 21221132 is about 4606.6399902749. The cubic root of 21221132 is about 276.8574294451.

Adding to 21221132 its reverse (23112212), we get a palindrome (44333344).

The spelling of 21221132 in words is "twenty-one million, two hundred twenty-one thousand, one hundred thirty-two".