638581200535 has 4 divisors (see below), whose sum is σ = 766297440648. Its totient is φ = 510864960424.

The previous prime is 638581200533. The next prime is 638581200539. The reversal of 638581200535 is 535002185836.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 638581200535 - 2¹ = 638581200533 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 (638581200533) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 63858120049 + ... + 63858120058.

It is an arithmetic number, because the mean of its divisors is an integer number (191574360162).

Almost surely, 2^638581200535 is an apocalyptic number.

638581200535 is a deficient number, since it is larger than the sum of its proper divisors (127716240113).

638581200535 is a wasteful number, since it uses less digits than its factorization.

638581200535 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127716240112.

The product of its (nonzero) digits is 864000, while the sum is 46.

The spelling of 638581200535 in words is "six hundred thirty-eight billion, five hundred eighty-one million, two hundred thousand, five hundred thirty-five".