664775651727646 has 16 divisors (see below), whose sum is σ = 997592234064480. Its totient is φ = 332244927675360.

The previous prime is 664775651727569. The next prime is 664775651727749. The reversal of 664775651727646 is 646727156577466.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 59363791 + ... + 69667861.

It is an arithmetic number, because the mean of its divisors is an integer number (62349514629030).

Almost surely, 2^{664775651727646} is an apocalyptic number.

664775651727646 is a deficient number, since it is larger than the sum of its proper divisors (332816582336834).

664775651727646 is a wasteful number, since it uses less digits than its factorization.

664775651727646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10317939.

The product of its digits is 14936140800, while the sum is 79.

The spelling of 664775651727646 in words is "six hundred sixty-four trillion, seven hundred seventy-five billion, six hundred fifty-one million, seven hundred twenty-seven thousand, six hundred forty-six".