664643044899 has 6 divisors (see below), whose sum is σ = 960039953756. Its totient is φ = 443095363260.

The previous prime is 664643044889. The next prime is 664643044921. The reversal of 664643044899 is 998440346466.

664643044899 is a `hidden beast` number, since 6 + 64 + 6 + 43 + 0 + 448 + 99 = 666.

It is not a de Polignac number, because 664643044899 - 2⁸ = 664643044643 is a prime.

It is a super-2 number, since 2×664643044899² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664643044859) 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 5 ways as a sum of consecutive naturals, for example, 36924613597 + ... + 36924613614.

Almost surely, 2^664643044899 is an apocalyptic number.

664643044899 is a deficient number, since it is larger than the sum of its proper divisors (295396908857).

664643044899 is a wasteful number, since it uses less digits than its factorization.

664643044899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73849227217 (or 73849227214 counting only the distinct ones).

The product of its (nonzero) digits is 107495424, while the sum is 63.

The spelling of 664643044899 in words is "six hundred sixty-four billion, six hundred forty-three million, forty-four thousand, eight hundred ninety-nine".