256242870 has 144 divisors (see below), whose sum is σ = 764629632. Its totient is φ = 59304960.

The previous prime is 256242859. The next prime is 256242893. The reversal of 256242870 is 78242652.

256242870 is a `hidden beast` number, since 2 + 5 + 624 + 28 + 7 + 0 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 258075 + ... + 259065.

It is an arithmetic number, because the mean of its divisors is an integer number (5309928).

Almost surely, 2^256242870 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 256242870, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (382314816).

256242870 is an abundant number, since it is smaller than the sum of its proper divisors (508386762).

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

256242870 is a wasteful number, since it uses less digits than its factorization.

256242870 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1047 (or 1031 counting only the distinct ones).

The product of its (nonzero) digits is 53760, while the sum is 36.

The square root of 256242870 is about 16007.5878882485. The cubic root of 256242870 is about 635.1611552863.

The spelling of 256242870 in words is "two hundred fifty-six million, two hundred forty-two thousand, eight hundred seventy".