1665166506 has 8 divisors (see below), whose sum is σ = 3330333024. Its totient is φ = 555055500.

The previous prime is 1665166429. The next prime is 1665166511. The reversal of 1665166506 is 6056615661.

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

1665166506 is an admirable number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 138763870 + ... + 138763881.

It is an arithmetic number, because the mean of its divisors is an integer number (416291628).

Almost surely, 2^1665166506 is an apocalyptic number.

1665166506 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1665166506 is a wasteful number, since it uses less digits than its factorization.

1665166506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 277527756.

The product of its (nonzero) digits is 194400, while the sum is 42.

The square root of 1665166506 is about 40806.4517692975. The cubic root of 1665166506 is about 1185.2752672849.

The spelling of 1665166506 in words is "one billion, six hundred sixty-five million, one hundred sixty-six thousand, five hundred six".