21201111222102 has 96 divisors (see below), whose sum is σ = 55299135640320. Its totient is φ = 5734690747200.

The previous prime is 21201111222073. The next prime is 21201111222169. The reversal of 21201111222102 is 20122211110212.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 422028 + ... + 6525360.

It is an arithmetic number, because the mean of its divisors is an integer number (576032662920).

Almost surely, 2^{21201111222102} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21201111222102, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27649567820160).

21201111222102 is an abundant number, since it is smaller than the sum of its proper divisors (34098024418218).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21201111222102 is a wasteful number, since it uses less digits than its factorization.

21201111222102 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6104818 (or 6104815 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21201111222102 its reverse (20122211110212), we get a palindrome (41323322332314).

The spelling of 21201111222102 in words is "twenty-one trillion, two hundred one billion, one hundred eleven million, two hundred twenty-two thousand, one hundred two".