64809954977 has 4 divisors (see below), whose sum is σ = 65222757396. Its totient is φ = 64397152560.

The previous prime is 64809954931. The next prime is 64809955037. The reversal of 64809954977 is 77945990846.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 77945990846 = 2 ⋅38972995423.

It can be written as a sum of positive squares in 2 ways, for example, as 32281668241 + 32528286736 = 179671^2 + 180356^2 .

It is a cyclic number.

It is not a de Polignac number, because 64809954977 - 2¹⁰ = 64809953953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64809954907) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 206400974 + ... + 206401287.

It is an arithmetic number, because the mean of its divisors is an integer number (16305689349).

Almost surely, 2^64809954977 is an apocalyptic number.

It is an amenable number.

64809954977 is a deficient number, since it is larger than the sum of its proper divisors (412802419).

64809954977 is a wasteful number, since it uses less digits than its factorization.

64809954977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 412802418.

The product of its (nonzero) digits is 137168640, while the sum is 68.

The spelling of 64809954977 in words is "sixty-four billion, eight hundred nine million, nine hundred fifty-four thousand, nine hundred seventy-seven".