66447365566 has 4 divisors (see below), whose sum is σ = 99671048352. Its totient is φ = 33223682782.

The previous prime is 66447365563. The next prime is 66447365591. The reversal of 66447365566 is 66556374466.

It is a happy number.

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

It is a self number, because there is not a number n which added to its sum of digits gives 66447365566.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66447365561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16611841390 + ... + 16611841393.

It is an arithmetic number, because the mean of its divisors is an integer number (24917762088).

Almost surely, 2^66447365566 is an apocalyptic number.

66447365566 is a deficient number, since it is larger than the sum of its proper divisors (33223682786).

66447365566 is a wasteful number, since it uses less digits than its factorization.

66447365566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33223682785.

The product of its digits is 65318400, while the sum is 58.

The spelling of 66447365566 in words is "sixty-six billion, four hundred forty-seven million, three hundred sixty-five thousand, five hundred sixty-six".