64666266266646 has 384 divisors, whose sum is σ = 167349615114240. Its totient is φ = 17840562432000.

The previous prime is 64666266266629. The next prime is 64666266266683.

64666266266646 is nontrivially palindromic in base 10.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 3107898775 + ... + 3107919581.

It is an arithmetic number, because the mean of its divisors is an integer number (435806289360).

Almost surely, 2^{64666266266646} is an apocalyptic number.

64666266266646 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 64666266266646, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (83674807557120).

64666266266646 is an abundant number, since it is smaller than the sum of its proper divisors (102683348847594).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

64666266266646 is a wasteful number, since it uses less digits than its factorization.

64666266266646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21212 (or 21209 counting only the distinct ones).

The product of its digits is 3869835264, while the sum is 72.

The spelling of 64666266266646 in words is "sixty-four trillion, six hundred sixty-six billion, two hundred sixty-six million, two hundred sixty-six thousand, six hundred forty-six".