256231040 has 192 divisors, whose sum is σ = 698855040. Its totient is φ = 89616384.

The previous prime is 256231033. The next prime is 256231067. The reversal of 256231040 is 40132652.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a junction number, because it is equal to n+sod(n) for n = 256230997 and 256231015.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2487629 + ... + 2487731.

It is an arithmetic number, because the mean of its divisors is an integer number (3639870).

Almost surely, 2^256231040 is an apocalyptic number.

256231040 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 256231040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (349427520).

256231040 is an abundant number, since it is smaller than the sum of its proper divisors (442624000).

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

256231040 is a wasteful number, since it uses less digits than its factorization.

256231040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171 (or 146 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 23.

The square root of 256231040 is about 16007.2183717222. The cubic root of 256231040 is about 635.1513806116.

Adding to 256231040 its reverse (40132652), we get a palindrome (296363692).

The spelling of 256231040 in words is "two hundred fifty-six million, two hundred thirty-one thousand, forty".