21111212011201 has 16 divisors (see below), whose sum is σ = 23700905238528. Its totient is φ = 18671931576000.

The previous prime is 21111212011199. The next prime is 21111212011223. The reversal of 21111212011201 is 10211021211112.

It is a cyclic number.

It is not a de Polignac number, because 21111212011201 - 2¹ = 21111212011199 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21111212011261) 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, 259291681 + ... + 259373086.

It is an arithmetic number, because the mean of its divisors is an integer number (1481306577408).

Almost surely, 2^{21111212011201} is an apocalyptic number.

It is an amenable number.

21111212011201 is a deficient number, since it is larger than the sum of its proper divisors (2589693227327).

21111212011201 is a wasteful number, since it uses less digits than its factorization.

21111212011201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 518664912.

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

Adding to 21111212011201 its reverse (10211021211112), we get a palindrome (31322233222313).

The spelling of 21111212011201 in words is "twenty-one trillion, one hundred eleven billion, two hundred twelve million, eleven thousand, two hundred one".