66005523646 has 4 divisors (see below), whose sum is σ = 99008285472. Its totient is φ = 33002761822.

The previous prime is 66005523593. The next prime is 66005523709. The reversal of 66005523646 is 64632550066.

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

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 as a sum of consecutive naturals, namely, 16501380910 + ... + 16501380913.

It is an arithmetic number, because the mean of its divisors is an integer number (24752071368).

Almost surely, 2^66005523646 is an apocalyptic number.

66005523646 is a deficient number, since it is larger than the sum of its proper divisors (33002761826).

66005523646 is a wasteful number, since it uses less digits than its factorization.

66005523646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33002761825.

The product of its (nonzero) digits is 777600, while the sum is 43.

The spelling of 66005523646 in words is "sixty-six billion, five million, five hundred twenty-three thousand, six hundred forty-six".