256430740 has 24 divisors (see below), whose sum is σ = 539237160. Its totient is φ = 102432768.

The previous prime is 256430719. The next prime is 256430809. The reversal of 256430740 is 47034652.

It can be written as a sum of positive squares in 4 ways, for example, as 64995844 + 191434896 = 8062^2 + 13836^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7044 + ... + 23716.

It is an arithmetic number, because the mean of its divisors is an integer number (22468215).

Almost surely, 2^256430740 is an apocalyptic number.

256430740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256430740 is an abundant number, since it is smaller than the sum of its proper divisors (282806420).

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

256430740 is a wasteful number, since it uses less digits than its factorization.

256430740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17451 (or 17449 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 31.

The square root of 256430740 is about 16013.4549676202. The cubic root of 256430740 is about 635.3163447433.

The spelling of 256430740 in words is "two hundred fifty-six million, four hundred thirty thousand, seven hundred forty".