55566166505 has 4 divisors (see below), whose sum is σ = 66679399812. Its totient is φ = 44452933200.

The previous prime is 55566166489. The next prime is 55566166529. The reversal of 55566166505 is 50566166555.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50566166555 = 5 ⋅10113233311.

It can be written as a sum of positive squares in 2 ways, for example, as 26394551296 + 29171615209 = 162464^2 + 170797^2 .

It is not a de Polignac number, because 55566166505 - 2⁴ = 55566166489 is a prime.

It is a super-2 number, since 2×55566166505² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5556616646 + ... + 5556616655.

It is an arithmetic number, because the mean of its divisors is an integer number (16669849953).

Almost surely, 2^55566166505 is an apocalyptic number.

It is an amenable number.

55566166505 is a deficient number, since it is larger than the sum of its proper divisors (11113233307).

55566166505 is a wasteful number, since it uses less digits than its factorization.

55566166505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11113233306.

The product of its (nonzero) digits is 4050000, while the sum is 50.

Adding to 55566166505 its sum of digits (50), we get a palindrome (55566166555).

The spelling of 55566166505 in words is "fifty-five billion, five hundred sixty-six million, one hundred sixty-six thousand, five hundred five".