211311222121 has 4 divisors (see below), whose sum is σ = 211532955732. Its totient is φ = 211089488512.

The previous prime is 211311222077. The next prime is 211311222131. The reversal of 211311222121 is 121222113112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 150205854096 + 61105368025 = 387564^2 + 247195^2 .

It is a cyclic number.

It is not a de Polignac number, because 211311222121 - 2⁷ = 211311221993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (211311222131) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 110865376 + ... + 110867281.

It is an arithmetic number, because the mean of its divisors is an integer number (52883238933).

Almost surely, 2^211311222121 is an apocalyptic number.

It is an amenable number.

211311222121 is a deficient number, since it is larger than the sum of its proper divisors (221733611).

211311222121 is an equidigital number, since it uses as much as digits as its factorization.

211311222121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 221733610.

The product of its digits is 96, while the sum is 19.

Adding to 211311222121 its reverse (121222113112), we get a palindrome (332533335233).

The spelling of 211311222121 in words is "two hundred eleven billion, three hundred eleven million, two hundred twenty-two thousand, one hundred twenty-one".