21944084 has 6 divisors (see below), whose sum is σ = 38402154. Its totient is φ = 10972040.

The previous prime is 21944081. The next prime is 21944089. The reversal of 21944084 is 48044912.

It can be written as a sum of positive squares in only one way, i.e., 21715600 + 228484 = 4660^2 + 478^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21944084.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21944081) 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 as a sum of consecutive naturals, namely, 2743007 + ... + 2743014.

It is an arithmetic number, because the mean of its divisors is an integer number (6400359).

Almost surely, 2^21944084 is an apocalyptic number.

It is an amenable number.

21944084 is a deficient number, since it is larger than the sum of its proper divisors (16458070).

21944084 is a wasteful number, since it uses less digits than its factorization.

21944084 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5486025 (or 5486023 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 32.

The square root of 21944084 is about 4684.4513019136. The cubic root of 21944084 is about 279.9663394910.

Adding to 21944084 its reverse (48044912), we get a palindrome (69988996).

The spelling of 21944084 in words is "twenty-one million, nine hundred forty-four thousand, eighty-four".