211121210321 has 6 divisors (see below), whose sum is σ = 245589979410. Its totient is φ = 180961037376.

The previous prime is 211121210317. The next prime is 211121210329. The reversal of 211121210321 is 123012121112.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 126127971025 + 84993239296 = 355145^2 + 291536^2 .

It is not a de Polignac number, because 211121210321 - 2² = 211121210317 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 211121210321.

It is not an unprimeable number, because it can be changed into a prime (211121210329) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2154298016 + ... + 2154298113.

It is an arithmetic number, because the mean of its divisors is an integer number (40931663235).

Almost surely, 2^211121210321 is an apocalyptic number.

It is an amenable number.

211121210321 is a deficient number, since it is larger than the sum of its proper divisors (34468769089).

211121210321 is an equidigital number, since it uses as much as digits as its factorization.

211121210321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4308596143 (or 4308596136 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 17.

Adding to 211121210321 its reverse (123012121112), we get a palindrome (334133331433).

The spelling of 211121210321 in words is "two hundred eleven billion, one hundred twenty-one million, two hundred ten thousand, three hundred twenty-one".