21002210199709 has 2 divisors, whose sum is σ = 21002210199710. Its totient is φ = 21002210199708.

The previous prime is 21002210199703. The next prime is 21002210199713. The reversal of 21002210199709 is 90799101220012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17382312024100 + 3619898175609 = 4169210^2 + 1902603^2 .

It is a cyclic number.

It is not a de Polignac number, because 21002210199709 - 2¹⁵ = 21002210166941 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21002210199703) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10501105099854 + 10501105099855.

It is an arithmetic number, because the mean of its divisors is an integer number (10501105099855).

Almost surely, 2^{21002210199709} is an apocalyptic number.

It is an amenable number.

21002210199709 is a deficient number, since it is larger than the sum of its proper divisors (1).

21002210199709 is an equidigital number, since it uses as much as digits as its factorization.

21002210199709 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40824, while the sum is 43.

The spelling of 21002210199709 in words is "twenty-one trillion, two billion, two hundred ten million, one hundred ninety-nine thousand, seven hundred nine".