21221332 has 24 divisors (see below), whose sum is σ = 41090112. Its totient is φ = 9508800.

The previous prime is 21221303. The next prime is 21221339. The reversal of 21221332 is 23312212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221339) 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, 273 + ... + 6520.

It is an arithmetic number, because the mean of its divisors is an integer number (1712088).

Almost surely, 2^21221332 is an apocalyptic number.

21221332 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21221332 is a deficient number, since it is larger than the sum of its proper divisors (19868780).

21221332 is a wasteful number, since it uses less digits than its factorization.

21221332 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6879 (or 6877 counting only the distinct ones).

The product of its digits is 144, while the sum is 16.

The square root of 21221332 is about 4606.6616980195. The cubic root of 21221332 is about 276.8582991963.

Adding to 21221332 its reverse (23312212), we get a palindrome (44533544).

The spelling of 21221332 in words is "twenty-one million, two hundred twenty-one thousand, three hundred thirty-two".