212121010121111 has 32 divisors (see below), whose sum is σ = 261489963571200. Its totient is φ = 167563353891456.

The previous prime is 212121010121099. The next prime is 212121010121117. The reversal of 212121010121111 is 111121010121212.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-212121010121111 is a prime.

It is a super-3 number, since 3×212121010121111³ (a number of 44 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 212121010121111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212121010121117) 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 31 ways as a sum of consecutive naturals, for example, 1186223270 + ... + 1186402076.

It is an arithmetic number, because the mean of its divisors is an integer number (8171561361600).

Almost surely, 2^{212121010121111} is an apocalyptic number.

212121010121111 is a deficient number, since it is larger than the sum of its proper divisors (49368953450089).

212121010121111 is a wasteful number, since it uses less digits than its factorization.

212121010121111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 199623.

The product of its (nonzero) digits is 16, while the sum is 17.

Adding to 212121010121111 its reverse (111121010121212), we get a palindrome (323242020242323).

The spelling of 212121010121111 in words is "two hundred twelve trillion, one hundred twenty-one billion, ten million, one hundred twenty-one thousand, one hundred eleven".