21938984 has 16 divisors (see below), whose sum is σ = 41217120. Its totient is φ = 10947760.

The previous prime is 21938971. The next prime is 21939007. The reversal of 21938984 is 48983912.

It is a happy number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 2069 + ... + 6939.

It is an arithmetic number, because the mean of its divisors is an integer number (2576070).

Almost surely, 2^21938984 is an apocalyptic number.

It is an amenable number.

21938984 is a deficient number, since it is larger than the sum of its proper divisors (19278136).

21938984 is a wasteful number, since it uses less digits than its factorization.

21938984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5440 (or 5436 counting only the distinct ones).

The product of its digits is 124416, while the sum is 44.

The square root of 21938984 is about 4683.9069162399. The cubic root of 21938984 is about 279.9446489227.

It can be divided in two parts, 21938 and 984, that added together give a palindrome (22922).

The spelling of 21938984 in words is "twenty-one million, nine hundred thirty-eight thousand, nine hundred eighty-four".