21020020100111 has 8 divisors (see below), whose sum is σ = 21174348754944. Its totient is φ = 20866030258360.

The previous prime is 21020020100099. The next prime is 21020020100119. The reversal of 21020020100111 is 11100102002012.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21020020100111 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21020020100092 and 21020020100101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21020020100119) 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, 84578735 + ... + 84826896.

It is an arithmetic number, because the mean of its divisors is an integer number (2646793594368).

Almost surely, 2^{21020020100111} is an apocalyptic number.

21020020100111 is a deficient number, since it is larger than the sum of its proper divisors (154328654833).

21020020100111 is a wasteful number, since it uses less digits than its factorization.

21020020100111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 169406541.

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

Adding to 21020020100111 its reverse (11100102002012), we get a palindrome (32120122102123).

The spelling of 21020020100111 in words is "twenty-one trillion, twenty billion, twenty million, one hundred thousand, one hundred eleven".