21944072 has 16 divisors (see below), whose sum is σ = 41461200. Its totient is φ = 10887760.

The previous prime is 21944057. The next prime is 21944081. The reversal of 21944072 is 27044912.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9422 + ... + 11517.

It is an arithmetic number, because the mean of its divisors is an integer number (2591325).

Almost surely, 2^21944072 is an apocalyptic number.

It is an amenable number.

21944072 is a deficient number, since it is larger than the sum of its proper divisors (19517128).

21944072 is a wasteful number, since it uses less digits than its factorization.

21944072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21076 (or 21072 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 29.

The square root of 21944072 is about 4684.4500210804. The cubic root of 21944072 is about 279.9662884584.

Adding to 21944072 its reverse (27044912), we get a palindrome (48988984).

The spelling of 21944072 in words is "twenty-one million, nine hundred forty-four thousand, seventy-two".