321105220145 has 4 divisors (see below), whose sum is σ = 385326264180. Its totient is φ = 256884176112.

The previous prime is 321105220141. The next prime is 321105220147. The reversal of 321105220145 is 541022501123.

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 219859707664 + 101245512481 = 468892^2 + 318191^2 .

It is a cyclic number.

It is not a de Polignac number, because 321105220145 - 2² = 321105220141 is a prime.

It is not an unprimeable number, because it can be changed into a prime (321105220141) 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, 32110522010 + ... + 32110522019.

It is an arithmetic number, because the mean of its divisors is an integer number (96331566045).

Almost surely, 2^321105220145 is an apocalyptic number.

It is an amenable number.

321105220145 is a deficient number, since it is larger than the sum of its proper divisors (64221044035).

321105220145 is an equidigital number, since it uses as much as digits as its factorization.

321105220145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64221044034.

The product of its (nonzero) digits is 2400, while the sum is 26.

Adding to 321105220145 its reverse (541022501123), we get a palindrome (862127721268).

The spelling of 321105220145 in words is "three hundred twenty-one billion, one hundred five million, two hundred twenty thousand, one hundred forty-five".