1666855005 has 8 divisors (see below), whose sum is σ = 2666968032. Its totient is φ = 888989328.

The previous prime is 1666854997. The next prime is 1666855007. The reversal of 1666855005 is 5005586661.

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

It is not a de Polignac number, because 1666855005 - 2³ = 1666854997 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1666855007) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55561819 + ... + 55561848.

It is an arithmetic number, because the mean of its divisors is an integer number (333371004).

Almost surely, 2^1666855005 is an apocalyptic number.

1666855005 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1666855005 is a deficient number, since it is larger than the sum of its proper divisors (1000113027).

1666855005 is a wasteful number, since it uses less digits than its factorization.

1666855005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111123675.

The product of its (nonzero) digits is 216000, while the sum is 42.

The square root of 1666855005 is about 40827.1356453034. The cubic root of 1666855005 is about 1185.6757597717.

The spelling of 1666855005 in words is "one billion, six hundred sixty-six million, eight hundred fifty-five thousand, five".