321312420 has 480 divisors, whose sum is σ = 1263588480. Its totient is φ = 67184640.

The previous prime is 321312389. The next prime is 321312487. The reversal of 321312420 is 24213123.

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 = 321312393 and 321312402.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 4401504 + ... + 4401576.

It is an arithmetic number, because the mean of its divisors is an integer number (2632476).

Almost surely, 2^321312420 is an apocalyptic number.

321312420 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 321312420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (631794240).

321312420 is an abundant number, since it is smaller than the sum of its proper divisors (942276060).

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

321312420 is a wasteful number, since it uses less digits than its factorization.

321312420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137 (or 126 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 321312420 is about 17925.1895387469. The cubic root of 321312420 is about 684.9241893120.

Adding to 321312420 its reverse (24213123), we get a palindrome (345525543).

The spelling of 321312420 in words is "three hundred twenty-one million, three hundred twelve thousand, four hundred twenty".