21894838 has 16 divisors (see below), whose sum is σ = 38064384. Its totient is φ = 9250920.

The previous prime is 21894751. The next prime is 21894839. The reversal of 21894838 is 83849812.

It is a junction number, because it is equal to n+sod(n) for n = 21894794 and 21894803.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21894839) 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 in 7 ways as a sum of consecutive naturals, for example, 10020 + ... + 12007.

It is an arithmetic number, because the mean of its divisors is an integer number (2379024).

Almost surely, 2^21894838 is an apocalyptic number.

21894838 is a deficient number, since it is larger than the sum of its proper divisors (16169546).

21894838 is a wasteful number, since it uses less digits than its factorization.

21894838 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22107.

The product of its digits is 110592, while the sum is 43.

The square root of 21894838 is about 4679.1920242709. The cubic root of 21894838 is about 279.7567530287.

The spelling of 21894838 in words is "twenty-one million, eight hundred ninety-four thousand, eight hundred thirty-eight".