21734189 has 2 divisors, whose sum is σ = 21734190. Its totient is φ = 21734188.

The previous prime is 21734173. The next prime is 21734191. The reversal of 21734189 is 98143712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10956100 + 10778089 = 3310^2 + 3283^2 .

It is a cyclic number.

It is not a de Polignac number, because 21734189 - 2⁴ = 21734173 is a prime.

Together with 21734191, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21734129) 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 as a sum of consecutive naturals, namely, 10867094 + 10867095.

It is an arithmetic number, because the mean of its divisors is an integer number (10867095).

Almost surely, 2^21734189 is an apocalyptic number.

It is an amenable number.

21734189 is a deficient number, since it is larger than the sum of its proper divisors (1).

21734189 is an equidigital number, since it uses as much as digits as its factorization.

21734189 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12096, while the sum is 35.

The square root of 21734189 is about 4661.9941012404. The cubic root of 21734189 is about 279.0708529686.

The spelling of 21734189 in words is "twenty-one million, seven hundred thirty-four thousand, one hundred eighty-nine".