21001101322021 has 16 divisors (see below), whose sum is σ = 22245827414400. Its totient is φ = 19784134326528.

The previous prime is 21001101322013. The next prime is 21001101322031. The reversal of 21001101322021 is 12022310110012.

It is a cyclic number.

It is not a de Polignac number, because 21001101322021 - 2³ = 21001101322013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21001101321986 and 21001101322004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001101322031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6140185 + ... + 8927713.

It is an arithmetic number, because the mean of its divisors is an integer number (1390364213400).

Almost surely, 2^{21001101322021} is an apocalyptic number.

It is an amenable number.

21001101322021 is a deficient number, since it is larger than the sum of its proper divisors (1244726092379).

21001101322021 is a wasteful number, since it uses less digits than its factorization.

21001101322021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2792508.

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 21001101322021 its reverse (12022310110012), we get a palindrome (33023411432033).

The spelling of 21001101322021 in words is "twenty-one trillion, one billion, one hundred one million, three hundred twenty-two thousand, twenty-one".