321220145540 has 48 divisors (see below), whose sum is σ = 770965410432. Its totient is φ = 110127326976.

The previous prime is 321220145527. The next prime is 321220145557. The reversal of 321220145540 is 45541022123.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3853139 + ... + 3935621.

It is an arithmetic number, because the mean of its divisors is an integer number (16061779384).

Almost surely, 2^321220145540 is an apocalyptic number.

It is an amenable number.

321220145540 is an abundant number, since it is smaller than the sum of its proper divisors (449745264892).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

321220145540 is a wasteful number, since it uses less digits than its factorization.

321220145540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110316 (or 110314 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 29.

Adding to 321220145540 its reverse (45541022123), we get a palindrome (366761167663).

The spelling of 321220145540 in words is "three hundred twenty-one billion, two hundred twenty million, one hundred forty-five thousand, five hundred forty".