256287380 has 24 divisors (see below), whose sum is σ = 539639520. Its totient is φ = 102241440.

The previous prime is 256287379. The next prime is 256287403. The reversal of 256287380 is 83782652.

It is a super-2 number, since 2×256287380² = 131366442294528800, which contains 22 as substring.

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, 9326 + ... + 24485.

It is an arithmetic number, because the mean of its divisors is an integer number (22484980).

Almost surely, 2^256287380 is an apocalyptic number.

256287380 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256287380 is an abundant number, since it is smaller than the sum of its proper divisors (283352140).

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

256287380 is a wasteful number, since it uses less digits than its factorization.

256287380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34199 (or 34197 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 41.

The square root of 256287380 is about 16008.9781060504. The cubic root of 256287380 is about 635.1979294950.

The spelling of 256287380 in words is "two hundred fifty-six million, two hundred eighty-seven thousand, three hundred eighty".