321280256 has 72 divisors (see below), whose sum is σ = 703855488. Its totient is φ = 145152000.

The previous prime is 321280243. The next prime is 321280273. The reversal of 321280256 is 652082123.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 762926 + ... + 763346.

Almost surely, 2^321280256 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 321280256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (351927744).

321280256 is an abundant number, since it is smaller than the sum of its proper divisors (382575232).

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

321280256 is a wasteful number, since it uses less digits than its factorization.

321280256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 719 (or 705 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 29.

The square root of 321280256 is about 17924.2923430745. The cubic root of 321280256 is about 684.9013344670.

The spelling of 321280256 in words is "three hundred twenty-one million, two hundred eighty thousand, two hundred fifty-six".