21110002021221 has 16 divisors (see below), whose sum is σ = 29721536990400. Its totient is φ = 13290574065408.

The previous prime is 21110002021151. The next prime is 21110002021349. The reversal of 21110002021221 is 12212020001112.

It is not a de Polignac number, because 21110002021221 - 2¹⁰ = 21110002020197 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21110002021221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21110002021421) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 584131636 + ... + 584167773.

It is an arithmetic number, because the mean of its divisors is an integer number (1857596061900).

Almost surely, 2^{21110002021221} is an apocalyptic number.

It is an amenable number.

21110002021221 is a deficient number, since it is larger than the sum of its proper divisors (8611534969179).

21110002021221 is a wasteful number, since it uses less digits than its factorization.

21110002021221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1168299748.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21110002021221 its reverse (12212020001112), we get a palindrome (33322022022333).

The spelling of 21110002021221 in words is "twenty-one trillion, one hundred ten billion, two million, twenty-one thousand, two hundred twenty-one".