211665420013 has 2 divisors, whose sum is σ = 211665420014. Its totient is φ = 211665420012.

The previous prime is 211665419971. The next prime is 211665420067. The reversal of 211665420013 is 310024566112.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 112668978244 + 98996441769 = 335662^2 + 314637^2 .

It is a cyclic number.

It is not a de Polignac number, because 211665420013 - 2²⁵ = 211631865581 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211665420413) 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, 105832710006 + 105832710007.

It is an arithmetic number, because the mean of its divisors is an integer number (105832710007).

Almost surely, 2^211665420013 is an apocalyptic number.

It is an amenable number.

211665420013 is a deficient number, since it is larger than the sum of its proper divisors (1).

211665420013 is an equidigital number, since it uses as much as digits as its factorization.

211665420013 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8640, while the sum is 31.

Adding to 211665420013 its reverse (310024566112), we get a palindrome (521689986125).

The spelling of 211665420013 in words is "two hundred eleven billion, six hundred sixty-five million, four hundred twenty thousand, thirteen".