21101021100101 has 4 divisors (see below), whose sum is σ = 21101031490572. Its totient is φ = 21101010709632.

The previous prime is 21101021100067. The next prime is 21101021100121. The reversal of 21101021100101 is 10100112010112.

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 6468751303876 + 14632269796225 = 2543374^2 + 3825215^2 .

It is a cyclic number.

It is not a de Polignac number, because 21101021100101 - 2⁶ = 21101021100037 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21101021100121) 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, 1042610 + ... + 6579443.

It is an arithmetic number, because the mean of its divisors is an integer number (5275257872643).

Almost surely, 2^{21101021100101} is an apocalyptic number.

It is an amenable number.

21101021100101 is a deficient number, since it is larger than the sum of its proper divisors (10390471).

21101021100101 is an equidigital number, since it uses as much as digits as its factorization.

21101021100101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10390470.

The product of its (nonzero) digits is 4, while the sum is 11.

Adding to 21101021100101 its reverse (10100112010112), we get a palindrome (31201133110213).

The spelling of 21101021100101 in words is "twenty-one trillion, one hundred one billion, twenty-one million, one hundred thousand, one hundred one".