638550857 has 8 divisors (see below), whose sum is σ = 730087296. Its totient is φ = 547093152.

The previous prime is 638550853. The next prime is 638550859. The reversal of 638550857 is 758055836.

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

It is a cyclic number.

It is not a de Polignac number, because 638550857 - 2² = 638550853 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (638550853) by changing a digit.

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, 1133 + ... + 35754.

It is an arithmetic number, because the mean of its divisors is an integer number (91260912).

Almost surely, 2^638550857 is an apocalyptic number.

It is an amenable number.

638550857 is a deficient number, since it is larger than the sum of its proper divisors (91536439).

638550857 is a wasteful number, since it uses less digits than its factorization.

638550857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39367.

The product of its (nonzero) digits is 1008000, while the sum is 47.

The square root of 638550857 is about 25269.5638466516. The cubic root of 638550857 is about 861.1229503150.

The spelling of 638550857 in words is "six hundred thirty-eight million, five hundred fifty thousand, eight hundred fifty-seven".