21436324 has 72 divisors (see below), whose sum is σ = 48263040. Its totient is φ = 8253504.

The previous prime is 21436319. The next prime is 21436333. The reversal of 21436324 is 42363412.

It is a plaindrome in base 11.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 119667 + ... + 119845.

It is an arithmetic number, because the mean of its divisors is an integer number (670320).

Almost surely, 2^21436324 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 21436324, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24131520).

21436324 is an abundant number, since it is smaller than the sum of its proper divisors (26826716).

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

21436324 is a wasteful number, since it uses less digits than its factorization.

21436324 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 257 (or 248 counting only the distinct ones).

The product of its digits is 3456, while the sum is 25.

The square root of 21436324 is about 4629.9377965584. The cubic root of 21436324 is about 277.7901043182.

Adding to 21436324 its reverse (42363412), we get a palindrome (63799736).

The spelling of 21436324 in words is "twenty-one million, four hundred thirty-six thousand, three hundred twenty-four".