66555166155566 has 8 divisors (see below), whose sum is σ = 108908453709144. Its totient is φ = 30252348252520.

The previous prime is 66555166155557. The next prime is 66555166155593.

It is a happy number.

66555166155566 is nontrivially palindromic in base 10.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×66555166155566² (a number of 28 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 66555166155496 and 66555166155505.

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 1512617412605 + ... + 1512617412648.

It is an arithmetic number, because the mean of its divisors is an integer number (13613556713643).

Almost surely, 2^{66555166155566} is an apocalyptic number.

66555166155566 is a deficient number, since it is larger than the sum of its proper divisors (42353287553578).

66555166155566 is a wasteful number, since it uses less digits than its factorization.

66555166155566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3025234825266.

The product of its digits is 729000000, while the sum is 68.

The spelling of 66555166155566 in words is "sixty-six trillion, five hundred fifty-five billion, one hundred sixty-six million, one hundred fifty-five thousand, five hundred sixty-six".