213111011121 has 4 divisors (see below), whose sum is σ = 284148014832. Its totient is φ = 142074007412.

The previous prime is 213111011107. The next prime is 213111011123. The reversal of 213111011121 is 121110111312.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 213111011121 - 2¹⁰ = 213111010097 is a prime.

It is a super-2 number, since 2×213111011121² (a number of 23 digits) contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 213111011121.

It is not an unprimeable number, because it can be changed into a prime (213111011123) 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 3 ways as a sum of consecutive naturals, for example, 35518501851 + ... + 35518501856.

It is an arithmetic number, because the mean of its divisors is an integer number (71037003708).

Almost surely, 2^213111011121 is an apocalyptic number.

It is an amenable number.

213111011121 is a deficient number, since it is larger than the sum of its proper divisors (71037003711).

213111011121 is an equidigital number, since it uses as much as digits as its factorization.

213111011121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71037003710.

The product of its (nonzero) digits is 12, while the sum is 15.

Adding to 213111011121 its reverse (121110111312), we get a palindrome (334221122433).

The spelling of 213111011121 in words is "two hundred thirteen billion, one hundred eleven million, eleven thousand, one hundred twenty-one".