21113532 has 108 divisors (see below), whose sum is σ = 60708648. Its totient is φ = 6177600.

The previous prime is 21113527. The next prime is 21113549. The reversal of 21113532 is 23531112.

21113532 is a `hidden beast` number, since 21 + 113 + 532 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 161107 + ... + 161237.

Almost surely, 2^21113532 is an apocalyptic number.

21113532 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21113532, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30354324).

21113532 is an abundant number, since it is smaller than the sum of its proper divisors (39595116).

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

21113532 is a wasteful number, since it uses less digits than its factorization.

21113532 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200 (or 184 counting only the distinct ones).

The product of its digits is 180, while the sum is 18.

The square root of 21113532 is about 4594.9463544203. The cubic root of 21113532 is about 276.3887087579.

Adding to 21113532 its reverse (23531112), we get a palindrome (44644644).

The spelling of 21113532 in words is "twenty-one million, one hundred thirteen thousand, five hundred thirty-two".