256311040 has 72 divisors (see below), whose sum is σ = 650114640. Its totient is φ = 96485376.

The previous prime is 256311031. The next prime is 256311047. The reversal of 256311040 is 40113652.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256311047) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15871 + ... + 27649.

It is an arithmetic number, because the mean of its divisors is an integer number (9029370).

Almost surely, 2^256311040 is an apocalyptic number.

256311040 is a gapful number since it is divisible by the number (20) 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 256311040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (325057320).

256311040 is an abundant number, since it is smaller than the sum of its proper divisors (393803600).

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

256311040 is a wasteful number, since it uses less digits than its factorization.

256311040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11817 (or 11803 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 256311040 is about 16009.7170493423. The cubic root of 256311040 is about 635.2174756786.

Adding to 256311040 its reverse (40113652), we get a palindrome (296424692).

The spelling of 256311040 in words is "two hundred fifty-six million, three hundred eleven thousand, forty".