66538883566 has 4 divisors (see below), whose sum is σ = 99808325352. Its totient is φ = 33269441782.

The previous prime is 66538883561. The next prime is 66538883603.

It is a happy number.

66538883566 is nontrivially palindromic in base 10.

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

It is a junction number, because it is equal to n+sod(n) for n = 66538883498 and 66538883507.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66538883561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16634720890 + ... + 16634720893.

It is an arithmetic number, because the mean of its divisors is an integer number (24952081338).

Almost surely, 2^66538883566 is an apocalyptic number.

66538883566 is a deficient number, since it is larger than the sum of its proper divisors (33269441786).

66538883566 is a wasteful number, since it uses less digits than its factorization.

66538883566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33269441785.

The product of its digits is 149299200, while the sum is 64.

The spelling of 66538883566 in words is "sixty-six billion, five hundred thirty-eight million, eight hundred eighty-three thousand, five hundred sixty-six".