21837089 has 2 divisors, whose sum is σ = 21837090. Its totient is φ = 21837088.

The previous prime is 21837073. The next prime is 21837091. The reversal of 21837089 is 98073812.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17572864 + 4264225 = 4192^2 + 2065^2 .

It is a cyclic number.

It is not a de Polignac number, because 21837089 - 2⁴ = 21837073 is a prime.

Together with 21837091, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21837019) by changing a digit.

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 as a sum of consecutive naturals, namely, 10918544 + 10918545.

It is an arithmetic number, because the mean of its divisors is an integer number (10918545).

Almost surely, 2^21837089 is an apocalyptic number.

It is an amenable number.

21837089 is a deficient number, since it is larger than the sum of its proper divisors (1).

21837089 is an equidigital number, since it uses as much as digits as its factorization.

21837089 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24192, while the sum is 38.

The square root of 21837089 is about 4673.0171195920. The cubic root of 21837089 is about 279.5105778428.

The spelling of 21837089 in words is "twenty-one million, eight hundred thirty-seven thousand, eighty-nine".