256442642 has 8 divisors (see below), whose sum is σ = 388986300. Its totient is φ = 126780544.

The previous prime is 256442623. The next prime is 256442653. The reversal of 256442642 is 246244652.

It can be written as a sum of positive squares in 2 ways, for example, as 200477281 + 55965361 = 14159^2 + 7481^2 .

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

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, 720167 + ... + 720522.

Almost surely, 2^256442642 is an apocalyptic number.

256442642 is a deficient number, since it is larger than the sum of its proper divisors (132543658).

256442642 is a wasteful number, since it uses less digits than its factorization.

256442642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1440780.

The product of its digits is 92160, while the sum is 35.

The square root of 256442642 is about 16013.8265882955. The cubic root of 256442642 is about 635.3261738017.

The spelling of 256442642 in words is "two hundred fifty-six million, four hundred forty-two thousand, six hundred forty-two".