21101221210110 has 64 divisors (see below), whose sum is σ = 52394417740800. Its totient is φ = 5432421036672.

The previous prime is 21101221210099. The next prime is 21101221210217. The reversal of 21101221210110 is 1101212210112.

It is a happy number.

It is a super-2 number, since 2×21101221210110² (a number of 27 digits) contains 22 as substring.

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

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21101221210110.

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, 7644597 + ... + 10032063.

It is an arithmetic number, because the mean of its divisors is an integer number (818662777200).

Almost surely, 2^{21101221210110} is an apocalyptic number.

21101221210110 is an abundant number, since it is smaller than the sum of its proper divisors (31293196530690).

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

21101221210110 is a wasteful number, since it uses less digits than its factorization.

21101221210110 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2397665.

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

Adding to 21101221210110 its reverse (1101212210112), we get a palindrome (22202433420222).

The spelling of 21101221210110 in words is "twenty-one trillion, one hundred one billion, two hundred twenty-one million, two hundred ten thousand, one hundred ten".