21826770 has 64 divisors (see below), whose sum is σ = 62484480. Its totient is φ = 4771008.

The previous prime is 21826751. The next prime is 21826771. The reversal of 21826770 is 7762812.

21826770 is nontrivially palindromic in base 13.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21826771) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2571 + ... + 7089.

It is an arithmetic number, because the mean of its divisors is an integer number (976320).

Almost surely, 2^21826770 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21826770, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31242240).

21826770 is an abundant number, since it is smaller than the sum of its proper divisors (40657710).

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

21826770 is a wasteful number, since it uses less digits than its factorization.

21826770 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4559.

The product of its (nonzero) digits is 9408, while the sum is 33.

The square root of 21826770 is about 4671.9128844618. The cubic root of 21826770 is about 279.4665438282.

The spelling of 21826770 in words is "twenty-one million, eight hundred twenty-six thousand, seven hundred seventy".