21834349 has 2 divisors, whose sum is σ = 21834350. Its totient is φ = 21834348.

The previous prime is 21834331. The next prime is 21834353. The reversal of 21834349 is 94343812.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15856324 + 5978025 = 3982^2 + 2445^2 .

It is a cyclic number.

It is not a de Polignac number, because 21834349 - 2¹⁵ = 21801581 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21837349) 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, 10917174 + 10917175.

It is an arithmetic number, because the mean of its divisors is an integer number (10917175).

Almost surely, 2^21834349 is an apocalyptic number.

It is an amenable number.

21834349 is a deficient number, since it is larger than the sum of its proper divisors (1).

21834349 is an equidigital number, since it uses as much as digits as its factorization.

21834349 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20736, while the sum is 34.

The square root of 21834349 is about 4672.7239379189. The cubic root of 21834349 is about 279.4988868612.

The spelling of 21834349 in words is "twenty-one million, eight hundred thirty-four thousand, three hundred forty-nine".