21220042110 has 64 divisors (see below), whose sum is σ = 53038152000. Its totient is φ = 5426849792.

The previous prime is 21220042091. The next prime is 21220042111. The reversal of 21220042110 is 1124002212.

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 21220042110.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220042111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 47782 + ... + 211478.

It is an arithmetic number, because the mean of its divisors is an integer number (828721125).

Almost surely, 2^21220042110 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21220042110, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26519076000).

21220042110 is an abundant number, since it is smaller than the sum of its proper divisors (31818109890).

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

21220042110 is a wasteful number, since it uses less digits than its factorization.

21220042110 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163885.

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 21220042110 its reverse (1124002212), we get a palindrome (22344044322).

The spelling of 21220042110 in words is "twenty-one billion, two hundred twenty million, forty-two thousand, one hundred ten".