1280621328 has 40 divisors (see below), whose sum is σ = 3780883008. Its totient is φ = 365891712.

The previous prime is 1280621291. The next prime is 1280621333. The reversal of 1280621328 is 8231260821.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1905351 + ... + 1906022.

Almost surely, 2^1280621328 is an apocalyptic number.

It is an amenable number.

1280621328 is an abundant number, since it is smaller than the sum of its proper divisors (2500261680).

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

1280621328 is a wasteful number, since it uses less digits than its factorization.

1280621328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3811391 (or 3811385 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 33.

The square root of 1280621328 is about 35785.7699092810. The cubic root of 1280621328 is about 1085.9426998518.

The spelling of 1280621328 in words is "one billion, two hundred eighty million, six hundred twenty-one thousand, three hundred twenty-eight".