321780330 has 64 divisors (see below), whose sum is σ = 876372480. Its totient is φ = 83979072.

The previous prime is 321780323. The next prime is 321780337. The reversal of 321780330 is 33087123.

321780330 is a `hidden beast` number, since 321 + 7 + 8 + 0 + 330 = 666.

It is an interprime number because it is at equal distance from previous prime (321780323) and next prime (321780337).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 321780294 and 321780303.

It is not an unprimeable number, because it can be changed into a prime (321780337) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12 + ... + 25368.

It is an arithmetic number, because the mean of its divisors is an integer number (13693320).

Almost surely, 2^321780330 is an apocalyptic number.

321780330 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 321780330, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (438186240).

321780330 is an abundant number, since it is smaller than the sum of its proper divisors (554592150).

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

321780330 is a wasteful number, since it uses less digits than its factorization.

321780330 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25420 (or 25414 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 27.

The square root of 321780330 is about 17938.2365354011. The cubic root of 321780330 is about 685.2565008111.

The spelling of 321780330 in words is "three hundred twenty-one million, seven hundred eighty thousand, three hundred thirty".