256006642 has 12 divisors (see below), whose sum is σ = 391400730. Its totient is φ = 125585408.

The previous prime is 256006637. The next prime is 256006643. The reversal of 256006642 is 246600652.

It can be written as a sum of positive squares in 3 ways, for example, as 252841801 + 3164841 = 15901^2 + 1779^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256006643) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 17167 + ... + 28402.

Almost surely, 2^256006642 is an apocalyptic number.

256006642 is a deficient number, since it is larger than the sum of its proper divisors (135394088).

256006642 is an equidigital number, since it uses as much as digits as its factorization.

256006642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45677 (or 45624 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 31.

The square root of 256006642 is about 16000.2075611537. The cubic root of 256006642 is about 634.9659121553.

The spelling of 256006642 in words is "two hundred fifty-six million, six thousand, six hundred forty-two".