1381328256 has 384 divisors, whose sum is σ = 4792596480. Its totient is φ = 344678400.

The previous prime is 1381328243. The next prime is 1381328293. The reversal of 1381328256 is 6528231831.

It is a tau number, because it is divible by the number of its divisors (384).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 10082620 + ... + 10082756.

It is an arithmetic number, because the mean of its divisors is an integer number (12480720).

Almost surely, 2^1381328256 is an apocalyptic number.

1381328256 is a gapful number since it is divisible by the number (16) 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 1381328256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2396298240).

1381328256 is an abundant number, since it is smaller than the sum of its proper divisors (3411268224).

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

1381328256 is a wasteful number, since it uses less digits than its factorization.

1381328256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214 (or 191 counting only the distinct ones).

The product of its digits is 69120, while the sum is 39.

The square root of 1381328256 is about 37166.2246670280. The cubic root of 1381328256 is about 1113.6933639848.

The spelling of 1381328256 in words is "one billion, three hundred eighty-one million, three hundred twenty-eight thousand, two hundred fifty-six".