64646555564647 has 8 divisors (see below), whose sum is σ = 75389569172000. Its totient is φ = 55411333340832.

The previous prime is 64646555564609. The next prime is 64646555564729. The reversal of 64646555564647 is 74646555564646.

It is not a de Polignac number, because 64646555564647 - 2²⁷ = 64646421346919 is a prime.

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 64646555564647.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64646555564447) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 94236961122 + ... + 94236961807.

It is an arithmetic number, because the mean of its divisors is an integer number (9423696146500).

Almost surely, 2^{64646555564647} is an apocalyptic number.

64646555564647 is a deficient number, since it is larger than the sum of its proper divisors (10743013607353).

64646555564647 is an equidigital number, since it uses as much as digits as its factorization.

64646555564647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 188473922950 (or 188473922936 counting only the distinct ones).

The product of its digits is 8709120000, while the sum is 73.

Subtracting 64646555564647 from its reverse (74646555564646), we obtain a palindrome (9999999999999).

The spelling of 64646555564647 in words is "sixty-four trillion, six hundred forty-six billion, five hundred fifty-five million, five hundred sixty-four thousand, six hundred forty-seven".