21726894 has 48 divisors (see below), whose sum is σ = 51349248. Its totient is φ = 6109488.

The previous prime is 21726893. The next prime is 21726931. The reversal of 21726894 is 49862712.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21726893) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 19147 + ... + 20249.

It is an arithmetic number, because the mean of its divisors is an integer number (1069776).

Almost surely, 2^21726894 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21726894, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25674624).

21726894 is an abundant number, since it is smaller than the sum of its proper divisors (29622354).

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

21726894 is a wasteful number, since it uses less digits than its factorization.

21726894 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1189 (or 1182 counting only the distinct ones).

The product of its digits is 48384, while the sum is 39.

The square root of 21726894 is about 4661.2116450554. The cubic root of 21726894 is about 279.0396264421.

The spelling of 21726894 in words is "twenty-one million, seven hundred twenty-six thousand, eight hundred ninety-four".