21221201100212 has 12 divisors (see below), whose sum is σ = 37325615134500. Its totient is φ = 10556739633216.

The previous prime is 21221201100199. The next prime is 21221201100221. The reversal of 21221201100212 is 21200110212212.

It can be written as a sum of positive squares in 2 ways, for example, as 14522608209316 + 6698592890896 = 3810854^2 + 2588164^2 .

It is a super-2 number, since 2×21221201100212² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13465228337 + ... + 13465229912.

It is an arithmetic number, because the mean of its divisors is an integer number (3110467927875).

Almost surely, 2^{21221201100212} is an apocalyptic number.

It is an amenable number.

21221201100212 is a deficient number, since it is larger than the sum of its proper divisors (16104414034288).

21221201100212 is a wasteful number, since it uses less digits than its factorization.

21221201100212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26930458450 (or 26930458448 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21221201100212 its reverse (21200110212212), we get a palindrome (42421311312424).

The spelling of 21221201100212 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred one million, one hundred thousand, two hundred twelve".