638348637 has 4 divisors (see below), whose sum is σ = 851131520. Its totient is φ = 425565756.

The previous prime is 638348629. The next prime is 638348653. The reversal of 638348637 is 736843836.

638348637 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 638348637 - 2³ = 638348629 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638348537) 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, 106391437 + ... + 106391442.

It is an arithmetic number, because the mean of its divisors is an integer number (212782880).

Almost surely, 2^638348637 is an apocalyptic number.

It is an amenable number.

638348637 is a deficient number, since it is larger than the sum of its proper divisors (212782883).

638348637 is a wasteful number, since it uses less digits than its factorization.

638348637 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212782882.

The product of its digits is 1741824, while the sum is 48.

The square root of 638348637 is about 25265.5622735771. The cubic root of 638348637 is about 861.0320389092.

The spelling of 638348637 in words is "six hundred thirty-eight million, three hundred forty-eight thousand, six hundred thirty-seven".