21126336 has 112 divisors (see below), whose sum is σ = 69738240. Its totient is φ = 5483520.

The previous prime is 21126317. The next prime is 21126337. The reversal of 21126336 is 63362112.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (112).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a nude number because it is divisible by every one of its digits.

21126336 is a modest number, since divided by 6336 gives 2112 as remainder.

It is not an unprimeable number, because it can be changed into a prime (21126337) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14070 + ... + 15498.

Almost surely, 2^21126336 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21126336, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34869120).

21126336 is an abundant number, since it is smaller than the sum of its proper divisors (48611904).

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

21126336 is a wasteful number, since it uses less digits than its factorization.

21126336 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1462 (or 1452 counting only the distinct ones).

The product of its digits is 1296, while the sum is 24.

The square root of 21126336 is about 4596.3394130547. The cubic root of 21126336 is about 276.4445681297. Note that the first 3 decimals are identical.

Adding to 21126336 its reverse (63362112), we get a palindrome (84488448).

It can be divided in two parts, 2112 and 6336, that added together give a palindrome (8448).

The spelling of 21126336 in words is "twenty-one million, one hundred twenty-six thousand, three hundred thirty-six".