21101201020111 has 4 divisors (see below), whose sum is σ = 21101300822800. Its totient is φ = 21101101217424.

The previous prime is 21101201020091. The next prime is 21101201020129. The reversal of 21101201020111 is 11102010210112.

It is a happy number.

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 21101201020111 - 2⁹ = 21101201019599 is a prime.

It is a super-2 number, since 2×21101201020111² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21101201020091 and 21101201020100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21101201027111) 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, 49583526 + ... + 50007283.

It is an arithmetic number, because the mean of its divisors is an integer number (5275325205700).

Almost surely, 2^{21101201020111} is an apocalyptic number.

21101201020111 is a deficient number, since it is larger than the sum of its proper divisors (99802689).

21101201020111 is an equidigital number, since it uses as much as digits as its factorization.

21101201020111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99802688.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 21101201020111 its reverse (11102010210112), we get a palindrome (32203211230223).

The spelling of 21101201020111 in words is "twenty-one trillion, one hundred one billion, two hundred one million, twenty thousand, one hundred eleven".