256105353240 has 192 divisors, whose sum is σ = 910182873600. Its totient is φ = 61937568000.

The previous prime is 256105353197. The next prime is 256105353367. The reversal of 256105353240 is 42353501652.

256105353240 is a `hidden beast` number, since 2 + 5 + 61 + 0 + 5 + 353 + 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 = 256105353195 and 256105353204.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1582065 + ... + 1736415.

It is an arithmetic number, because the mean of its divisors is an integer number (4740535800).

Almost surely, 2^256105353240 is an apocalyptic number.

256105353240 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 256105353240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (455091436800).

256105353240 is an abundant number, since it is smaller than the sum of its proper divisors (654077520360).

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

256105353240 is a wasteful number, since it uses less digits than its factorization.

256105353240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 154798 (or 154791 counting only the distinct ones).

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

Adding to 256105353240 its reverse (42353501652), we get a palindrome (298458854892).

The spelling of 256105353240 in words is "two hundred fifty-six billion, one hundred five million, three hundred fifty-three thousand, two hundred forty".