638005001005 has 4 divisors (see below), whose sum is σ = 765606001212. Its totient is φ = 510404000800.

The previous prime is 638005000991. The next prime is 638005001041. The reversal of 638005001005 is 500100500836.

638005001005 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.

It can be written as a sum of positive squares in 2 ways, for example, as 308499152329 + 329505848676 = 555427^2 + 574026^2 .

It is not a de Polignac number, because 638005001005 - 2²³ = 637996612397 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 63800500096 + ... + 63800500105.

It is an arithmetic number, because the mean of its divisors is an integer number (191401500303).

Almost surely, 2^638005001005 is an apocalyptic number.

It is an amenable number.

638005001005 is a deficient number, since it is larger than the sum of its proper divisors (127601000207).

638005001005 is a wasteful number, since it uses less digits than its factorization.

638005001005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 127601000206.

The product of its (nonzero) digits is 3600, while the sum is 28.

The spelling of 638005001005 in words is "six hundred thirty-eight billion, five million, one thousand, five".