640486815488871 has 8 divisors (see below), whose sum is σ = 919673376086640. Its totient is φ = 394145732608512.

The previous prime is 640486815488809. The next prime is 640486815488909. The reversal of 640486815488871 is 178884518684046.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 640486815488871 - 2²⁶ = 640486748380007 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640486815488771) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8211369429306 + ... + 8211369429383.

It is an arithmetic number, because the mean of its divisors is an integer number (114959172010830).

Almost surely, 2^{640486815488871} is an apocalyptic number.

640486815488871 is a deficient number, since it is larger than the sum of its proper divisors (279186560597769).

640486815488871 is a wasteful number, since it uses less digits than its factorization.

640486815488871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16422738858705.

The product of its (nonzero) digits is 2642411520, while the sum is 78.

The spelling of 640486815488871 in words is "six hundred forty trillion, four hundred eighty-six billion, eight hundred fifteen million, four hundred eighty-eight thousand, eight hundred seventy-one".