21111101221210 has 256 divisors, whose sum is σ = 53739868815360. Its totient is φ = 5750643133440.

The previous prime is 21111101221193. The next prime is 21111101221277. The reversal of 21111101221210 is 1212210111112.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 311307127 + ... + 311374933.

It is an arithmetic number, because the mean of its divisors is an integer number (209921362560).

Almost surely, 2^{21111101221210} is an apocalyptic number.

21111101221210 is an abundant number, since it is smaller than the sum of its proper divisors (32628767594150).

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

21111101221210 is a wasteful number, since it uses less digits than its factorization.

21111101221210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69501.

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

Adding to 21111101221210 its reverse (1212210111112), we get a palindrome (22323311332322).

The spelling of 21111101221210 in words is "twenty-one trillion, one hundred eleven billion, one hundred one million, two hundred twenty-one thousand, two hundred ten".