256789490 has 24 divisors (see below), whose sum is σ = 478668420. Its totient is φ = 99068480.

The previous prime is 256789483. The next prime is 256789501. The reversal of 256789490 is 94987652.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 144408289 + 112381201 = 12017^2 + 10601^2 .

It is an alternating number because its digits alternate between even and odd.

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 11 ways as a sum of consecutive naturals, for example, 272420 + ... + 273360.

Almost surely, 2^256789490 is an apocalyptic number.

256789490 is a deficient number, since it is larger than the sum of its proper divisors (221878930).

256789490 is an frugal number, since it uses more digits than its factorization.

256789490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1918 (or 977 counting only the distinct ones).

The product of its (nonzero) digits is 1088640, while the sum is 50.

The square root of 256789490 is about 16024.6525703367. The cubic root of 256789490 is about 635.6124786801.

The spelling of 256789490 in words is "two hundred fifty-six million, seven hundred eighty-nine thousand, four hundred ninety".