21212032 has 16 divisors (see below), whose sum is σ = 42258600. Its totient is φ = 10605952.

The previous prime is 21212017. The next prime is 21212033. The reversal of 21212032 is 23021212.

It is a tau number, because it is divible by the number of its divisors (16).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21212033) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82732 + ... + 82987.

Almost surely, 2^21212032 is an apocalyptic number.

It is an amenable number.

21212032 is a deficient number, since it is larger than the sum of its proper divisors (21046568).

21212032 is an equidigital number, since it uses as much as digits as its factorization.

21212032 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165733 (or 165721 counting only the distinct ones).

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

The square root of 21212032 is about 4605.6521796592. The cubic root of 21212032 is about 276.8178499855.

Adding to 21212032 its reverse (23021212), we get a palindrome (44233244).

The spelling of 21212032 in words is "twenty-one million, two hundred twelve thousand, thirty-two".