321220135420 has 12 divisors (see below), whose sum is σ = 674562284424. Its totient is φ = 128488054160.

The previous prime is 321220135403. The next prime is 321220135427. The reversal of 321220135420 is 24531022123.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (321220135427) 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, 8030503366 + ... + 8030503405.

It is an arithmetic number, because the mean of its divisors is an integer number (56213523702).

Almost surely, 2^321220135420 is an apocalyptic number.

It is an amenable number.

321220135420 is an abundant number, since it is smaller than the sum of its proper divisors (353342149004).

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

321220135420 is a wasteful number, since it uses less digits than its factorization.

321220135420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16061006780 (or 16061006778 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 25.

Adding to 321220135420 its reverse (24531022123), we get a palindrome (345751157543).

The spelling of 321220135420 in words is "three hundred twenty-one billion, two hundred twenty million, one hundred thirty-five thousand, four hundred twenty".