638283805 has 4 divisors (see below), whose sum is σ = 765940572. Its totient is φ = 510627040.

The previous prime is 638283761. The next prime is 638283817. The reversal of 638283805 is 508382836.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 265755204 + 372528601 = 16302^2 + 19301^2 .

It is not a de Polignac number, because 638283805 - 2¹⁵ = 638251037 is a prime.

It is a Duffinian number.

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 3 ways as a sum of consecutive naturals, for example, 63828376 + ... + 63828385.

It is an arithmetic number, because the mean of its divisors is an integer number (191485143).

Almost surely, 2^638283805 is an apocalyptic number.

It is an amenable number.

638283805 is a deficient number, since it is larger than the sum of its proper divisors (127656767).

638283805 is a wasteful number, since it uses less digits than its factorization.

638283805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127656766.

The product of its (nonzero) digits is 276480, while the sum is 43.

The square root of 638283805 is about 25264.2792297742. The cubic root of 638283805 is about 861.0028885276.

The spelling of 638283805 in words is "six hundred thirty-eight million, two hundred eighty-three thousand, eight hundred five".