21020100012221 has 16 divisors (see below), whose sum is σ = 21436791264000. Its totient is φ = 20607090604800.

The previous prime is 21020100012209. The next prime is 21020100012229. The reversal of 21020100012221 is 12221000102012.

It is a cyclic number.

It is not a de Polignac number, because 21020100012221 - 2¹⁴ = 21020099995837 is a prime.

It is a super-3 number, since 3×21020100012221³ (a number of 41 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21020100012196 and 21020100012205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21020100012229) 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, 7714181 + ... + 10077141.

It is an arithmetic number, because the mean of its divisors is an integer number (1339799454000).

Almost surely, 2^{21020100012221} is an apocalyptic number.

It is an amenable number.

21020100012221 is a deficient number, since it is larger than the sum of its proper divisors (416691251779).

21020100012221 is a wasteful number, since it uses less digits than its factorization.

21020100012221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2363740.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21020100012221 its reverse (12221000102012), we get a palindrome (33241100114233).

The spelling of 21020100012221 in words is "twenty-one trillion, twenty billion, one hundred million, twelve thousand, two hundred twenty-one".