21201112120110 has 64 divisors (see below), whose sum is σ = 54798762779712. Its totient is φ = 5218540793856.

The previous prime is 21201112120087. The next prime is 21201112120121. The reversal of 21201112120110 is 1102121110212.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21201112120110.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9607422 + ... + 11606238.

It is an arithmetic number, because the mean of its divisors is an integer number (856230668433).

Almost surely, 2^{21201112120110} is an apocalyptic number.

21201112120110 is an abundant number, since it is smaller than the sum of its proper divisors (33597650659602).

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

21201112120110 is a wasteful number, since it uses less digits than its factorization.

21201112120110 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2026037.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 21201112120110 its reverse (1102121110212), we get a palindrome (22303233230322).

The spelling of 21201112120110 in words is "twenty-one trillion, two hundred one billion, one hundred twelve million, one hundred twenty thousand, one hundred ten".