21833839 has 4 divisors (see below), whose sum is σ = 22586760. Its totient is φ = 21080920.

The previous prime is 21833821. The next prime is 21833857. The reversal of 21833839 is 93833812.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (21833821) and next prime (21833857).

It is a cyclic number.

It is not a de Polignac number, because 21833839 - 2⁵ = 21833807 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21833798 and 21833807.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21833039) 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 3 ways as a sum of consecutive naturals, for example, 376417 + ... + 376474.

It is an arithmetic number, because the mean of its divisors is an integer number (5646690).

Almost surely, 2^21833839 is an apocalyptic number.

21833839 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

21833839 is a deficient number, since it is larger than the sum of its proper divisors (752921).

21833839 is an equidigital number, since it uses as much as digits as its factorization.

21833839 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 752920.

The product of its digits is 31104, while the sum is 37.

The square root of 21833839 is about 4672.6693655768. The cubic root of 21833839 is about 279.4967106946.

The spelling of 21833839 in words is "twenty-one million, eight hundred thirty-three thousand, eight hundred thirty-nine".