21200120111 has 8 divisors (see below), whose sum is σ = 21501293184. Its totient is φ = 20899018840.

The previous prime is 21200120087. The next prime is 21200120159. The reversal of 21200120111 is 11102100212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21200120111 - 2²⁶ = 21133011247 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21200120092 and 21200120101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21200120171) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 924956 + ... + 947598.

It is an arithmetic number, because the mean of its divisors is an integer number (2687661648).

Almost surely, 2^21200120111 is an apocalyptic number.

21200120111 is a deficient number, since it is larger than the sum of its proper divisors (301173073).

21200120111 is a wasteful number, since it uses less digits than its factorization.

21200120111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35901.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21200120111 its reverse (11102100212), we get a palindrome (32302220323).

The spelling of 21200120111 in words is "twenty-one billion, two hundred million, one hundred twenty thousand, one hundred eleven".