21011732 has 12 divisors (see below), whose sum is σ = 42023520. Its totient is φ = 9005016.

The previous prime is 21011713. The next prime is 21011741. The reversal of 21011732 is 23711012.

21011732 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 21011732.

It is a congruent number.

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, 375182 + ... + 375237.

It is an arithmetic number, because the mean of its divisors is an integer number (3501960).

Almost surely, 2^21011732 is an apocalyptic number.

It is an amenable number.

21011732 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21011732 is a wasteful number, since it uses less digits than its factorization.

21011732 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 750430 (or 750428 counting only the distinct ones).

The product of its (nonzero) digits is 84, while the sum is 17.

The square root of 21011732 is about 4583.8555823673. The cubic root of 21011732 is about 275.9437853726.

Adding to 21011732 its reverse (23711012), we get a palindrome (44722744).

The spelling of 21011732 in words is "twenty-one million, eleven thousand, seven hundred thirty-two".