21010101200111 has 4 divisors (see below), whose sum is σ = 21010353472224. Its totient is φ = 21009848928000.

The previous prime is 21010101200017. The next prime is 21010101200161. The reversal of 21010101200111 is 11100210101012.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21010101200111 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21010101200092 and 21010101200101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21010101200161) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 126011090 + ... + 126177711.

It is an arithmetic number, because the mean of its divisors is an integer number (5252588368056).

Almost surely, 2^{21010101200111} is an apocalyptic number.

21010101200111 is a deficient number, since it is larger than the sum of its proper divisors (252272113).

21010101200111 is an equidigital number, since it uses as much as digits as its factorization.

21010101200111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 252272112.

The product of its (nonzero) digits is 4, while the sum is 11.

Adding to 21010101200111 its reverse (11100210101012), we get a palindrome (32110311301123).

The spelling of 21010101200111 in words is "twenty-one trillion, ten billion, one hundred one million, two hundred thousand, one hundred eleven".