21643314 has 64 divisors (see below), whose sum is σ = 54743040. Its totient is φ = 5541120.

The previous prime is 21643313. The next prime is 21643331. The reversal of 21643314 is 41334612.

It is not an unprimeable number, because it can be changed into a prime (21643313) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 36202 + ... + 36794.

It is an arithmetic number, because the mean of its divisors is an integer number (855360).

Almost surely, 2^21643314 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21643314, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27371520).

21643314 is an abundant number, since it is smaller than the sum of its proper divisors (33099726).

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

21643314 is a wasteful number, since it uses less digits than its factorization.

21643314 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 695.

The product of its digits is 1728, while the sum is 24.

The square root of 21643314 is about 4652.2375261803. The cubic root of 21643314 is about 278.6813592242.

Adding to 21643314 its reverse (41334612), we get a palindrome (62977926).

The spelling of 21643314 in words is "twenty-one million, six hundred forty-three thousand, three hundred fourteen".