641874854065 has 4 divisors (see below), whose sum is σ = 770249824884. Its totient is φ = 513499883248.

The previous prime is 641874854039. The next prime is 641874854129. The reversal of 641874854065 is 560458478146.

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

It can be written as a sum of positive squares in 2 ways, for example, as 71626352161 + 570248501904 = 267631^2 + 755148^2 .

It is a cyclic number.

It is not a de Polignac number, because 641874854065 - 2¹³ = 641874845873 is a prime.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

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, 64187485402 + ... + 64187485411.

It is an arithmetic number, because the mean of its divisors is an integer number (192562456221).

Almost surely, 2^641874854065 is an apocalyptic number.

It is an amenable number.

641874854065 is a deficient number, since it is larger than the sum of its proper divisors (128374970819).

641874854065 is a wasteful number, since it uses less digits than its factorization.

641874854065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128374970818.

The product of its (nonzero) digits is 25804800, while the sum is 58.

The spelling of 641874854065 in words is "six hundred forty-one billion, eight hundred seventy-four million, eight hundred fifty-four thousand, sixty-five".