21001111222110 has 16 divisors (see below), whose sum is σ = 50402666933136. Its totient is φ = 5600296325888.

The previous prime is 21001111222109. The next prime is 21001111222129. The reversal of 21001111222110 is 1122211110012.

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 21001111222110.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 350018520339 + ... + 350018520398.

It is an arithmetic number, because the mean of its divisors is an integer number (3150166683321).

Almost surely, 2^{21001111222110} is an apocalyptic number.

21001111222110 is an abundant number, since it is smaller than the sum of its proper divisors (29401555711026).

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

21001111222110 is a wasteful number, since it uses less digits than its factorization.

21001111222110 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 700037040747.

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

Adding to 21001111222110 its reverse (1122211110012), we get a palindrome (22123322332122).

The spelling of 21001111222110 in words is "twenty-one trillion, one billion, one hundred eleven million, two hundred twenty-two thousand, one hundred ten".