21000212212111 has 16 divisors (see below), whose sum is σ = 23009877660960. Its totient is φ = 19007309704320.

The previous prime is 21000212212103. The next prime is 21000212212151. The reversal of 21000212212111 is 11121221200012.

It is a cyclic number.

It is not a de Polignac number, because 21000212212111 - 2³ = 21000212212103 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21000212212151) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 187491121 + ... + 187603093.

It is an arithmetic number, because the mean of its divisors is an integer number (1438117353810).

Almost surely, 2^{21000212212111} is an apocalyptic number.

21000212212111 is a deficient number, since it is larger than the sum of its proper divisors (2009665448849).

21000212212111 is a wasteful number, since it uses less digits than its factorization.

21000212212111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 186666.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21000212212111 its reverse (11121221200012), we get a palindrome (32121433412123).

The spelling of 21000212212111 in words is "twenty-one trillion, two hundred twelve million, two hundred twelve thousand, one hundred eleven".