321220400 has 60 divisors (see below), whose sum is σ = 779470944. Its totient is φ = 127200000.

The previous prime is 321220397. The next prime is 321220409. The reversal of 321220400 is 4022123.

It is not an unprimeable number, because it can be changed into a prime (321220409) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 36425 + ... + 44375.

Almost surely, 2^321220400 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 321220400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (389735472).

321220400 is an abundant number, since it is smaller than the sum of its proper divisors (458250544).

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

321220400 is a wasteful number, since it uses less digits than its factorization.

321220400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8070 (or 8059 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 14.

The square root of 321220400 is about 17922.6225759513. The cubic root of 321220400 is about 684.8587983948.

Adding to 321220400 its reverse (4022123), we get a palindrome (325242523).

The spelling of 321220400 in words is "three hundred twenty-one million, two hundred twenty thousand, four hundred".