638103313 has 4 divisors (see below), whose sum is σ = 675638820. Its totient is φ = 600567808.

The previous prime is 638103307. The next prime is 638103379. The reversal of 638103313 is 313301836.

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 178944129 + 459159184 = 13377^2 + 21428^2 .

It is a cyclic number.

It is not a de Polignac number, because 638103313 - 2⁵ = 638103281 is a prime.

It is not an unprimeable number, because it can be changed into a prime (638103383) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18767728 + ... + 18767761.

It is an arithmetic number, because the mean of its divisors is an integer number (168909705).

Almost surely, 2^638103313 is an apocalyptic number.

It is an amenable number.

638103313 is a deficient number, since it is larger than the sum of its proper divisors (37535507).

638103313 is a wasteful number, since it uses less digits than its factorization.

638103313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37535506.

The product of its (nonzero) digits is 3888, while the sum is 28.

The square root of 638103313 is about 25260.7068982640. The cubic root of 638103313 is about 860.9217235961.

The spelling of 638103313 in words is "six hundred thirty-eight million, one hundred three thousand, three hundred thirteen".