21200899 has 2 divisors, whose sum is σ = 21200900. Its totient is φ = 21200898.

The previous prime is 21200897. The next prime is 21200911. The reversal of 21200899 is 99800212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21200899 - 2¹ = 21200897 is a prime.

Together with 21200897, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21200899.

It is not a weakly prime, because it can be changed into another prime (21200897) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10600449 + 10600450.

It is an arithmetic number, because the mean of its divisors is an integer number (10600450).

Almost surely, 2^21200899 is an apocalyptic number.

21200899 is a deficient number, since it is larger than the sum of its proper divisors (1).

21200899 is an equidigital number, since it uses as much as digits as its factorization.

21200899 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592, while the sum is 31.

The square root of 21200899 is about 4604.4433974152. The cubic root of 21200899 is about 276.7694128149.

The spelling of 21200899 in words is "twenty-one million, two hundred thousand, eight hundred ninety-nine".