21365299 has 2 divisors, whose sum is σ = 21365300. Its totient is φ = 21365298.

The previous prime is 21365269. The next prime is 21365303. The reversal of 21365299 is 99256312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21365299 - 2¹³ = 21357107 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21365219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10682649 + 10682650.

It is an arithmetic number, because the mean of its divisors is an integer number (10682650).

Almost surely, 2^21365299 is an apocalyptic number.

21365299 is a deficient number, since it is larger than the sum of its proper divisors (1).

21365299 is an equidigital number, since it uses as much as digits as its factorization.

21365299 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 29160, while the sum is 37.

The square root of 21365299 is about 4622.2612431579. The cubic root of 21365299 is about 277.4829640815.

The spelling of 21365299 in words is "twenty-one million, three hundred sixty-five thousand, two hundred ninety-nine".