664838655065 has 32 divisors (see below), whose sum is σ = 865444909056. Its totient is φ = 487382572800.

The previous prime is 664838655023. The next prime is 664838655083. The reversal of 664838655065 is 560556838466.

It is not a de Polignac number, because 664838655065 - 2⁶ = 664838655001 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 664838654989 and 664838655007.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9256040 + ... + 9327590.

It is an arithmetic number, because the mean of its divisors is an integer number (27045153408).

Almost surely, 2^664838655065 is an apocalyptic number.

664838655065 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

664838655065 is a deficient number, since it is larger than the sum of its proper divisors (200606253991).

664838655065 is a wasteful number, since it uses less digits than its factorization.

664838655065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72609.

The product of its (nonzero) digits is 124416000, while the sum is 62.

The spelling of 664838655065 in words is "six hundred sixty-four billion, eight hundred thirty-eight million, six hundred fifty-five thousand, sixty-five".