21302219 has 2 divisors, whose sum is σ = 21302220. Its totient is φ = 21302218.

The previous prime is 21302191. The next prime is 21302221. The reversal of 21302219 is 91220312.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21302219 is a prime.

It is a super-2 number, since 2×21302219² = 907569068647922, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 21302221, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21302219.

It is not a weakly prime, because it can be changed into another prime (21302279) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10651109 + 10651110.

It is an arithmetic number, because the mean of its divisors is an integer number (10651110).

Almost surely, 2^21302219 is an apocalyptic number.

21302219 is a deficient number, since it is larger than the sum of its proper divisors (1).

21302219 is an equidigital number, since it uses as much as digits as its factorization.

21302219 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 21302219 is about 4615.4326991085. The cubic root of 21302219 is about 277.2096099246.

The spelling of 21302219 in words is "twenty-one million, three hundred two thousand, two hundred nineteen".