64617397805 has 16 divisors (see below), whose sum is σ = 79049855664. Its totient is φ = 50689067520.

The previous prime is 64617397763. The next prime is 64617397811. The reversal of 64617397805 is 50879371646.

It can be written as a sum of positive squares in 8 ways, for example, as 20485051876 + 44132345929 = 143126^2 + 210077^2 .

It is a de Polignac number, because none of the positive numbers 2^k-64617397805 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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, 391337 + ... + 531393.

It is an arithmetic number, because the mean of its divisors is an integer number (4940615979).

Almost surely, 2^64617397805 is an apocalyptic number.

It is an amenable number.

64617397805 is a deficient number, since it is larger than the sum of its proper divisors (14432457859).

64617397805 is a wasteful number, since it uses less digits than its factorization.

64617397805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141856.

The product of its (nonzero) digits is 7620480, while the sum is 56.

The spelling of 64617397805 in words is "sixty-four billion, six hundred seventeen million, three hundred ninety-seven thousand, eight hundred five".