21332736 has 108 divisors (see below), whose sum is σ = 63135072. Its totient is φ = 6924288.

The previous prime is 21332711. The next prime is 21332761. The reversal of 21332736 is 63723312.

It is an interprime number because it is at equal distance from previous prime (21332711) and next prime (21332761).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 108190 + ... + 108386.

It is an arithmetic number, because the mean of its divisors is an integer number (584584).

Almost surely, 2^21332736 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 21332736, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31567536).

21332736 is an abundant number, since it is smaller than the sum of its proper divisors (41802336).

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

21332736 is a wasteful number, since it uses less digits than its factorization.

21332736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 266 (or 249 counting only the distinct ones).

The product of its digits is 4536, while the sum is 27.

The square root of 21332736 is about 4618.7374898342. The cubic root of 21332736 is about 277.3419211673.

The spelling of 21332736 in words is "twenty-one million, three hundred thirty-two thousand, seven hundred thirty-six".