256533510240 has 576 divisors, whose sum is σ = 1089889758720. Its totient is φ = 56085765120.

The previous prime is 256533510229. The next prime is 256533510349. The reversal of 256533510240 is 42015335652.

256533510240 is a `hidden beast` number, since 2 + 5 + 65 + 3 + 351 + 0 + 240 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 256533510195 and 256533510204.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 4842295 + ... + 4894985.

It is an arithmetic number, because the mean of its divisors is an integer number (1892169720).

Almost surely, 2^256533510240 is an apocalyptic number.

256533510240 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 256533510240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (544944879360).

256533510240 is an abundant number, since it is smaller than the sum of its proper divisors (833356248480).

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

256533510240 is a wasteful number, since it uses less digits than its factorization.

256533510240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52752 (or 52731 counting only the distinct ones).

The product of its (nonzero) digits is 108000, while the sum is 36.

Adding to 256533510240 its reverse (42015335652), we get a palindrome (298548845892).

The spelling of 256533510240 in words is "two hundred fifty-six billion, five hundred thirty-three million, five hundred ten thousand, two hundred forty".