256530240 has 168 divisors, whose sum is σ = 915314400. Its totient is φ = 68387328.

The previous prime is 256530233. The next prime is 256530269. The reversal of 256530240 is 42035652.

256530240 is a `hidden beast` number, since 2 + 5 + 653 + 0 + 2 + 4 + 0 = 666.

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 (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 76111 + ... + 79409.

It is an arithmetic number, because the mean of its divisors is an integer number (5448300).

Almost surely, 2^256530240 is an apocalyptic number.

256530240 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 256530240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (457657200).

256530240 is an abundant number, since it is smaller than the sum of its proper divisors (658784160).

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

256530240 is an equidigital number, since it uses as much as digits as its factorization.

256530240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3331 (or 3309 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 27.

The square root of 256530240 is about 16016.5614287212. The cubic root of 256530240 is about 635.3985057224.

Adding to 256530240 its reverse (42035652), we get a palindrome (298565892).

The spelling of 256530240 in words is "two hundred fifty-six million, five hundred thirty thousand, two hundred forty".