646871005 has 8 divisors (see below), whose sum is σ = 846813024. Its totient is φ = 470451600.

The previous prime is 646870999. The next prime is 646871009. The reversal of 646871005 is 500178646.

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

It is not a de Polignac number, because 646871005 - 2²⁵ = 613316573 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 (646871009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5880591 + ... + 5880700.

It is an arithmetic number, because the mean of its divisors is an integer number (105851628).

Almost surely, 2^646871005 is an apocalyptic number.

It is an amenable number.

646871005 is a deficient number, since it is larger than the sum of its proper divisors (199942019).

646871005 is a wasteful number, since it uses less digits than its factorization.

646871005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11761307.

The product of its (nonzero) digits is 40320, while the sum is 37.

The square root of 646871005 is about 25433.6588991832. The cubic root of 646871005 is about 864.8468906057.

The spelling of 646871005 in words is "six hundred forty-six million, eight hundred seventy-one thousand, five".