21043682 has 16 divisors (see below), whose sum is σ = 34575552. Its totient is φ = 9526320.

The previous prime is 21043681. The next prime is 21043691. The reversal of 21043682 is 28634012.

It is not an unprimeable number, because it can be changed into a prime (21043681) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3968 + ... + 7604.

It is an arithmetic number, because the mean of its divisors is an integer number (2160972).

Almost surely, 2^21043682 is an apocalyptic number.

21043682 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21043682 is a deficient number, since it is larger than the sum of its proper divisors (13531870).

21043682 is a wasteful number, since it uses less digits than its factorization.

21043682 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3913.

The product of its (nonzero) digits is 2304, while the sum is 26.

The square root of 21043682 is about 4587.3393159870. The cubic root of 21043682 is about 276.0835793225.

Adding to 21043682 its reverse (28634012), we get a palindrome (49677694).

The spelling of 21043682 in words is "twenty-one million, forty-three thousand, six hundred eighty-two".