664776808841 has 16 divisors (see below), whose sum is σ = 690847390464. Its totient is φ = 639201389904.

The previous prime is 664776808789. The next prime is 664776808847. The reversal of 664776808841 is 148808677466.

It is a cyclic number.

It is not a de Polignac number, because 664776808841 - 2⁶ = 664776808777 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664776808847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4312010 + ... + 4463516.

It is an arithmetic number, because the mean of its divisors is an integer number (43177961904).

Almost surely, 2^664776808841 is an apocalyptic number.

It is an amenable number.

664776808841 is a deficient number, since it is larger than the sum of its proper divisors (26070581623).

664776808841 is a wasteful number, since it uses less digits than its factorization.

664776808841 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153140.

The product of its (nonzero) digits is 86704128, while the sum is 65.

The spelling of 664776808841 in words is "six hundred sixty-four billion, seven hundred seventy-six million, eight hundred eight thousand, eight hundred forty-one".