21001102102221 has 8 divisors (see below), whose sum is σ = 28001617164960. Its totient is φ = 14000660887152.

The previous prime is 21001102102219. The next prime is 21001102102223. The reversal of 21001102102221 is 12220120110012.

It is an interprime number because it is at equal distance from previous prime (21001102102219) and next prime (21001102102223).

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

It is not a de Polignac number, because 21001102102221 - 2¹ = 21001102102219 is a prime.

It is a super-2 number, since 2×21001102102221² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21001102102221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001102102223) 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, 17794911 + ... + 18938348.

It is an arithmetic number, because the mean of its divisors is an integer number (3500202145620).

Almost surely, 2^{21001102102221} is an apocalyptic number.

It is an amenable number.

21001102102221 is a deficient number, since it is larger than the sum of its proper divisors (7000515062739).

21001102102221 is a wasteful number, since it uses less digits than its factorization.

21001102102221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36923835.

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

Adding to 21001102102221 its reverse (12220120110012), we get a palindrome (33221222212233).

The spelling of 21001102102221 in words is "twenty-one trillion, one billion, one hundred two million, one hundred two thousand, two hundred twenty-one".