21212220220110 has 32 divisors (see below), whose sum is σ = 56565920587680. Its totient is φ = 5656592058624.

The previous prime is 21212220220069. The next prime is 21212220220129. The reversal of 21212220220110 is 1102202221212.

It is a happy number.

21212220220110 is a `hidden beast` number, since 2 + 1 + 212 + 220 + 220 + 1 + 10 = 666.

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 15 ways as a sum of consecutive naturals, for example, 39281889027 + ... + 39281889566.

It is an arithmetic number, because the mean of its divisors is an integer number (1767685018365).

Almost surely, 2^{21212220220110} is an apocalyptic number.

21212220220110 is an abundant number, since it is smaller than the sum of its proper divisors (35353700367570).

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

21212220220110 is a wasteful number, since it uses less digits than its factorization.

21212220220110 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78563778609 (or 78563778603 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 21212220220110 its reverse (1102202221212), we get a palindrome (22314422441322).

The spelling of 21212220220110 in words is "twenty-one trillion, two hundred twelve billion, two hundred twenty million, two hundred twenty thousand, one hundred ten".