21036832 has 24 divisors (see below), whose sum is σ = 42846300. Its totient is φ = 10155264.

The previous prime is 21036811. The next prime is 21036833. The reversal of 21036832 is 23863012.

It can be written as a sum of positive squares in 2 ways, for example, as 18974736 + 2062096 = 4356^2 + 1436^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21036797 and 21036806.

It is not an unprimeable number, because it can be changed into a prime (21036833) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 10407 + ... + 12262.

Almost surely, 2^21036832 is an apocalyptic number.

It is an amenable number.

21036832 is an abundant number, since it is smaller than the sum of its proper divisors (21809468).

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

21036832 is a wasteful number, since it uses less digits than its factorization.

21036832 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22708 (or 22700 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 21036832 is about 4586.5926350615. The cubic root of 21036832 is about 276.0536197721.

Adding to 21036832 its reverse (23863012), we get a palindrome (44899844).

The spelling of 21036832 in words is "twenty-one million, thirty-six thousand, eight hundred thirty-two".