256730 has 8 divisors (see below), whose sum is σ = 462132. Its totient is φ = 102688.

The previous prime is 256723. The next prime is 256757. The reversal of 256730 is 37652.

It can be written as a sum of positive squares in 2 ways, for example, as 253009 + 3721 = 503^2 + 61^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a nialpdrome in base 8.

It is a junction number, because it is equal to n+sod(n) for n = 256696 and 256705.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12827 + ... + 12846.

2²⁵⁶⁷³⁰ is an apocalyptic number.

256730 is a deficient number, since it is larger than the sum of its proper divisors (205402).

256730 is a wasteful number, since it uses less digits than its factorization.

256730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25680.

The product of its (nonzero) digits is 1260, while the sum is 23.

The square root of 256730 is about 506.6853066747. The cubic root of 256730 is about 63.5563391122.

The spelling of 256730 in words is "two hundred fifty-six thousand, seven hundred thirty".