638508812363 has 4 divisors (see below), whose sum is σ = 638866923408. Its totient is φ = 638150701320.

The previous prime is 638508812327. The next prime is 638508812387. The reversal of 638508812363 is 363218805836.

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 638508812363 - 2³⁶ = 569789335627 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (638508812393) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 179052848 + ... + 179056413.

It is an arithmetic number, because the mean of its divisors is an integer number (159716730852).

Almost surely, 2^638508812363 is an apocalyptic number.

638508812363 is a deficient number, since it is larger than the sum of its proper divisors (358111045).

638508812363 is a wasteful number, since it uses less digits than its factorization.

638508812363 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 358111044.

The product of its (nonzero) digits is 4976640, while the sum is 53.

The spelling of 638508812363 in words is "six hundred thirty-eight billion, five hundred eight million, eight hundred twelve thousand, three hundred sixty-three".