64563706666 has 16 divisors (see below), whose sum is σ = 102547078920. Its totient is φ = 30381521920.

The previous prime is 64563706657. The next prime is 64563706679. The reversal of 64563706666 is 66660736546.

It can be written as a sum of positive squares in 4 ways, for example, as 63061756641 + 1501950025 = 251121^2 + 38755^2 .

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 1344600 + ... + 1391788.

Almost surely, 2^64563706666 is an apocalyptic number.

64563706666 is a deficient number, since it is larger than the sum of its proper divisors (37983372254).

64563706666 is a wasteful number, since it uses less digits than its factorization.

64563706666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87449.

The product of its (nonzero) digits is 19595520, while the sum is 55.

The spelling of 64563706666 in words is "sixty-four billion, five hundred sixty-three million, seven hundred six thousand, six hundred sixty-six".