1280344320 has 360 divisors, whose sum is σ = 4687779096. Its totient is φ = 333545472.

The previous prime is 1280344319. The next prime is 1280344333. The reversal of 1280344320 is 234430821.

It can be written as a sum of positive squares in 4 ways, for example, as 95883264 + 1184461056 = 9792^2 + 34416^2 .

It is a tau number, because it is divible by the number of its divisors (360).

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 5494924 + ... + 5495156.

Almost surely, 2^1280344320 is an apocalyptic number.

1280344320 is a gapful number since it is divisible by the number (10) 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 1280344320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2343889548).

1280344320 is an abundant number, since it is smaller than the sum of its proper divisors (3407434776).

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

1280344320 is an equidigital number, since it uses as much as digits as its factorization.

1280344320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 319 (or 296 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 27.

The square root of 1280344320 is about 35781.8993347195. The cubic root of 1280344320 is about 1085.8643950214.

The spelling of 1280344320 in words is "one billion, two hundred eighty million, three hundred forty-four thousand, three hundred twenty".