21677344 has 48 divisors (see below), whose sum is σ = 46484928. Its totient is φ = 9891072.

The previous prime is 21677333. The next prime is 21677353. The reversal of 21677344 is 44377612.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44269 + ... + 44755.

It is an arithmetic number, because the mean of its divisors is an integer number (968436).

Almost surely, 2^21677344 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 21677344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23242464).

21677344 is an abundant number, since it is smaller than the sum of its proper divisors (24807584).

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

21677344 is a wasteful number, since it uses less digits than its factorization.

21677344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 617 (or 609 counting only the distinct ones).

The product of its digits is 28224, while the sum is 34.

The square root of 21677344 is about 4655.8934695717. The cubic root of 21677344 is about 278.8273405751.

The spelling of 21677344 in words is "twenty-one million, six hundred seventy-seven thousand, three hundred forty-four".