321222400 has 108 divisors (see below), whose sum is σ = 810932472. Its totient is φ = 125931520.

The previous prime is 321222397. The next prime is 321222409. The reversal of 321222400 is 4222123.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (321222409) 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, 338727 + ... + 339673.

It is an arithmetic number, because the mean of its divisors is an integer number (7508634).

Almost surely, 2^321222400 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 321222400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (405466236).

321222400 is an abundant number, since it is smaller than the sum of its proper divisors (489710072).

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

321222400 is an equidigital number, since it uses as much as digits as its factorization.

321222400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1026 (or 1007 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 321222400 is about 17922.6783712703. The cubic root of 321222400 is about 684.8602197603.

Adding to 321222400 its reverse (4222123), we get a palindrome (325444523).

The spelling of 321222400 in words is "three hundred twenty-one million, two hundred twenty-two thousand, four hundred".