21001100002021 has 8 divisors (see below), whose sum is σ = 21003837182720. Its totient is φ = 20998363015008.

The previous prime is 21001100001979. The next prime is 21001100002037. The reversal of 21001100002021 is 12020000110012.

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

It is a cyclic number.

It is not a de Polignac number, because 21001100002021 - 2¹¹ = 21001099999973 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21001100001989 and 21001100002007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001100012021) 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, 404564950 + ... + 404616856.

It is an arithmetic number, because the mean of its divisors is an integer number (2625479647840).

Almost surely, 2^{21001100002021} is an apocalyptic number.

It is an amenable number.

21001100002021 is a deficient number, since it is larger than the sum of its proper divisors (2737180699).

21001100002021 is a wasteful number, since it uses less digits than its factorization.

21001100002021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96843.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 21001100002021 its reverse (12020000110012), we get a palindrome (33021100112033).

The spelling of 21001100002021 in words is "twenty-one trillion, one billion, one hundred million, two thousand, twenty-one".