321404220 has 192 divisors, whose sum is σ = 1036385280. Its totient is φ = 82656000.

The previous prime is 321404203. The next prime is 321404257. The reversal of 321404220 is 22404123.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 321404193 and 321404202.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3182170 + ... + 3182270.

It is an arithmetic number, because the mean of its divisors is an integer number (5397840).

Almost surely, 2^321404220 is an apocalyptic number.

321404220 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 321404220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (518192640).

321404220 is an abundant number, since it is smaller than the sum of its proper divisors (714981060).

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

321404220 is a wasteful number, since it uses less digits than its factorization.

321404220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 273 (or 265 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 321404220 is about 17927.7499982569. The cubic root of 321404220 is about 684.9894114548.

Adding to 321404220 its reverse (22404123), we get a palindrome (343808343).

The spelling of 321404220 in words is "three hundred twenty-one million, four hundred four thousand, two hundred twenty".