21845983 has 2 divisors, whose sum is σ = 21845984. Its totient is φ = 21845982.

The previous prime is 21845981. The next prime is 21846031. The reversal of 21845983 is 38954812.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21845983 - 2¹ = 21845981 is a prime.

Together with 21845981, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21845981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10922991 + 10922992.

It is an arithmetic number, because the mean of its divisors is an integer number (10922992).

Almost surely, 2^21845983 is an apocalyptic number.

21845983 is a deficient number, since it is larger than the sum of its proper divisors (1).

21845983 is an equidigital number, since it uses as much as digits as its factorization.

21845983 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 69120, while the sum is 40.

The square root of 21845983 is about 4673.9686562920. The cubic root of 21845983 is about 279.5485198606.

The spelling of 21845983 in words is "twenty-one million, eight hundred forty-five thousand, nine hundred eighty-three".