21339349 has 2 divisors, whose sum is σ = 21339350. Its totient is φ = 21339348.

The previous prime is 21339323. The next prime is 21339371. The reversal of 21339349 is 94393312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13176900 + 8162449 = 3630^2 + 2857^2 .

It is a cyclic number.

It is not a de Polignac number, because 21339349 - 2⁵ = 21339317 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21339379) 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, 10669674 + 10669675.

It is an arithmetic number, because the mean of its divisors is an integer number (10669675).

Almost surely, 2^21339349 is an apocalyptic number.

It is an amenable number.

21339349 is a deficient number, since it is larger than the sum of its proper divisors (1).

21339349 is an equidigital number, since it uses as much as digits as its factorization.

21339349 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 17496, while the sum is 34.

The square root of 21339349 is about 4619.4533226346. The cubic root of 21339349 is about 277.3705762297.

The spelling of 21339349 in words is "twenty-one million, three hundred thirty-nine thousand, three hundred forty-nine".