21210101101212 has 24 divisors (see below), whose sum is σ = 49504212346512. Its totient is φ = 7068037065600.

The previous prime is 21210101101207. The next prime is 21210101101223. The reversal of 21210101101212 is 21210110101212.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21210101101191 and 21210101101200.

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, 249535089 + ... + 249620072.

It is an arithmetic number, because the mean of its divisors is an integer number (2062675514438).

Almost surely, 2^{21210101101212} is an apocalyptic number.

It is an amenable number.

21210101101212 is an abundant number, since it is smaller than the sum of its proper divisors (28294111245300).

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

21210101101212 is a wasteful number, since it uses less digits than its factorization.

21210101101212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 499158709 (or 499158707 counting only the distinct ones).

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

Adding to 21210101101212 its reverse (21210110101212), we get a palindrome (42420211202424).

Subtracting 21210101101212 from its reverse (21210110101212), we obtain a square (9000000 = 3000²).

The spelling of 21210101101212 in words is "twenty-one trillion, two hundred ten billion, one hundred one million, one hundred one thousand, two hundred twelve".