646854875645 has 16 divisors (see below), whose sum is σ = 891359830080. Its totient is φ = 445679913600.

The previous prime is 646854875633. The next prime is 646854875647. The reversal of 646854875645 is 546578458646.

It is not a de Polignac number, because 646854875645 - 2³⁶ = 578135398909 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646854875647) 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 15 ways as a sum of consecutive naturals, for example, 309498896 + ... + 309500985.

It is an arithmetic number, because the mean of its divisors is an integer number (55709989380).

Almost surely, 2^646854875645 is an apocalyptic number.

It is an amenable number.

646854875645 is a deficient number, since it is larger than the sum of its proper divisors (244504954435).

646854875645 is a wasteful number, since it uses less digits than its factorization.

646854875645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 618999916.

The product of its digits is 774144000, while the sum is 68.

The spelling of 646854875645 in words is "six hundred forty-six billion, eight hundred fifty-four million, eight hundred seventy-five thousand, six hundred forty-five".