21000120220111 has 24 divisors (see below), whose sum is σ = 22657897149680. Its totient is φ = 19409334452352.

The previous prime is 21000120220091. The next prime is 21000120220127. The reversal of 21000120220111 is 11102202100012.

It is not a de Polignac number, because 21000120220111 - 2⁹ = 21000120219599 is a prime.

It is a super-2 number, since 2×21000120220111² (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 = 21000120220091 and 21000120220100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21000120220181) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12337645 + ... + 13936201.

Almost surely, 2^{21000120220111} is an apocalyptic number.

21000120220111 is a deficient number, since it is larger than the sum of its proper divisors (1657776929569).

21000120220111 is a wasteful number, since it uses less digits than its factorization.

21000120220111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1598983 (or 1598936 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21000120220111 its reverse (11102202100012), we get a palindrome (32102322320123).

The spelling of 21000120220111 in words is "twenty-one trillion, one hundred twenty million, two hundred twenty thousand, one hundred eleven".