21010201111 has 4 divisors (see below), whose sum is σ = 22246095312. Its totient is φ = 19774306912.

The previous prime is 21010201063. The next prime is 21010201133. The reversal of 21010201111 is 11110201012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21010201111 - 2⁷ = 21010200983 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21010201711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 617947075 + ... + 617947108.

It is an arithmetic number, because the mean of its divisors is an integer number (5561523828).

Almost surely, 2^21010201111 is an apocalyptic number.

21010201111 is a deficient number, since it is larger than the sum of its proper divisors (1235894201).

21010201111 is a wasteful number, since it uses less digits than its factorization.

21010201111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1235894200.

The product of its (nonzero) digits is 4, while the sum is 10.

Adding to 21010201111 its reverse (11110201012), we get a palindrome (32120402123).

Subtracting from 21010201111 its reverse (11110201012), we obtain a palindrome (9900000099).

The spelling of 21010201111 in words is "twenty-one billion, ten million, two hundred one thousand, one hundred eleven".