64811953684666 has 4 divisors (see below), whose sum is σ = 97217930527002. Its totient is φ = 32405976842332.

The previous prime is 64811953684657. The next prime is 64811953684721. The reversal of 64811953684666 is 66648635911846.

64811953684666 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 54680330998225 + 10131622686441 = 7394615^2 + 3183021^2 .

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 as a sum of consecutive naturals, namely, 16202988421165 + ... + 16202988421168.

Almost surely, 2^{64811953684666} is an apocalyptic number.

64811953684666 is a deficient number, since it is larger than the sum of its proper divisors (32405976842336).

64811953684666 is a wasteful number, since it uses less digits than its factorization.

64811953684666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32405976842335.

The product of its digits is 1074954240, while the sum is 73.

The spelling of 64811953684666 in words is "sixty-four trillion, eight hundred eleven billion, nine hundred fifty-three million, six hundred eighty-four thousand, six hundred sixty-six".