321220870666 has 12 divisors (see below), whose sum is σ = 508525562322. Its totient is φ = 152157254184.

The previous prime is 321220870631. The next prime is 321220870669. The reversal of 321220870666 is 666078022123.

It can be written as a sum of positive squares in only one way, i.e., 176459645041 + 144761225625 = 420071^2 + 380475^2 .

It is not an unprimeable number, because it can be changed into a prime (321220870669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 222451405 + ... + 222452848.

Almost surely, 2^321220870666 is an apocalyptic number.

321220870666 is a deficient number, since it is larger than the sum of its proper divisors (187304691656).

321220870666 is a wasteful number, since it uses less digits than its factorization.

321220870666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 444904293 (or 444904274 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 43.

Adding to 321220870666 its reverse (666078022123), we get a palindrome (987298892789).

The spelling of 321220870666 in words is "three hundred twenty-one billion, two hundred twenty million, eight hundred seventy thousand, six hundred sixty-six".