21302111 has 2 divisors, whose sum is σ = 21302112. Its totient is φ = 21302110.

The previous prime is 21302093. The next prime is 21302123. The reversal of 21302111 is 11120312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21302111 - 2¹⁰ = 21301087 is a prime.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 21302092 and 21302101.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21302161) 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, 10651055 + 10651056.

It is an arithmetic number, because the mean of its divisors is an integer number (10651056).

Almost surely, 2^21302111 is an apocalyptic number.

21302111 is a deficient number, since it is larger than the sum of its proper divisors (1).

21302111 is an equidigital number, since it uses as much as digits as its factorization.

21302111 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12, while the sum is 11.

The square root of 21302111 is about 4615.4209992156. The cubic root of 21302111 is about 277.2091414493.

Adding to 21302111 its reverse (11120312), we get a palindrome (32422423).

The spelling of 21302111 in words is "twenty-one million, three hundred two thousand, one hundred eleven".