211101102020021 has 4 divisors (see below), whose sum is σ = 211101131083500. Its totient is φ = 211101072956544.

The previous prime is 211101102019999. The next prime is 211101102020101. The reversal of 211101102020021 is 120020201101112.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 114379581235921 + 96721520784100 = 10694839^2 + 9834710^2 .

It is a cyclic number.

It is not a de Polignac number, because 211101102020021 - 2³⁴ = 211083922150837 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 211101102019978 and 211101102020005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211101102010021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6868055 + ... + 21665003.

It is an arithmetic number, because the mean of its divisors is an integer number (52775282770875).

Almost surely, 2^{211101102020021} is an apocalyptic number.

It is an amenable number.

211101102020021 is a deficient number, since it is larger than the sum of its proper divisors (29063479).

211101102020021 is a wasteful number, since it uses less digits than its factorization.

211101102020021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29063478.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 211101102020021 its reverse (120020201101112), we get a palindrome (331121303121133).

The spelling of 211101102020021 in words is "two hundred eleven trillion, one hundred one billion, one hundred two million, twenty thousand, twenty-one".