1306391328 has 192 divisors, whose sum is σ = 4210496640. Its totient is φ = 395642880.

The previous prime is 1306391327. The next prime is 1306391357. The reversal of 1306391328 is 8231936031.

1306391328 is a `hidden beast` number, since 1 + 3 + 0 + 639 + 13 + 2 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1306391292 and 1306391301.

It is not an unprimeable number, because it can be changed into a prime (1306391327) 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, 768976 + ... + 770672.

It is an arithmetic number, because the mean of its divisors is an integer number (21929670).

Almost surely, 2^1306391328 is an apocalyptic number.

1306391328 is a gapful number since it is divisible by the number (18) 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 1306391328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2105248320).

1306391328 is an abundant number, since it is smaller than the sum of its proper divisors (2904105312).

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

1306391328 is an equidigital number, since it uses as much as digits as its factorization.

1306391328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1739 (or 1713 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 36.

The square root of 1306391328 is about 36144.0358565559. The cubic root of 1306391328 is about 1093.1785368129.

The spelling of 1306391328 in words is "one billion, three hundred six million, three hundred ninety-one thousand, three hundred twenty-eight".