664775651727755 has 4 divisors (see below), whose sum is σ = 797730782073312. Its totient is φ = 531820521382200.

The previous prime is 664775651727749. The next prime is 664775651727757. The reversal of 664775651727755 is 557727156577466.

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

It is not a de Polignac number, because 664775651727755 - 2¹⁰ = 664775651726731 is a prime.

It is a super-2 number, since 2×664775651727755² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 664775651727755.

It is not an unprimeable number, because it can be changed into a prime (664775651727757) 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 3 ways as a sum of consecutive naturals, for example, 66477565172771 + ... + 66477565172780.

It is an arithmetic number, because the mean of its divisors is an integer number (199432695518328).

Almost surely, 2^{664775651727755} is an apocalyptic number.

664775651727755 is a deficient number, since it is larger than the sum of its proper divisors (132955130345557).

664775651727755 is a wasteful number, since it uses less digits than its factorization.

664775651727755 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132955130345556.

The product of its digits is 18151560000, while the sum is 80.

The spelling of 664775651727755 in words is "six hundred sixty-four trillion, seven hundred seventy-five billion, six hundred fifty-one million, seven hundred twenty-seven thousand, seven hundred fifty-five".