256501740 has 96 divisors (see below), whose sum is σ = 802690560. Its totient is φ = 60659200.

The previous prime is 256501717. The next prime is 256501741. The reversal of 256501740 is 47105652.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 256501698 and 256501707.

It is not an unprimeable number, because it can be changed into a prime (256501741) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 22321 + ... + 31799.

It is an arithmetic number, because the mean of its divisors is an integer number (8361360).

Almost surely, 2^256501740 is an apocalyptic number.

256501740 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 256501740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (401345280).

256501740 is an abundant number, since it is smaller than the sum of its proper divisors (546188820).

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

256501740 is a wasteful number, since it uses less digits than its factorization.

256501740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9543 (or 9541 counting only the distinct ones).

The product of its (nonzero) digits is 8400, while the sum is 30.

The square root of 256501740 is about 16015.6716999319. The cubic root of 256501740 is about 635.3749743471.

The spelling of 256501740 in words is "two hundred fifty-six million, five hundred one thousand, seven hundred forty".