1666718275 has 6 divisors (see below), whose sum is σ = 2066730692. Its totient is φ = 1333374600.

The previous prime is 1666718257. The next prime is 1666718297. The reversal of 1666718275 is 5728176661.

It is a happy number.

It is not a de Polignac number, because 1666718275 - 2⁷ = 1666718147 is a prime.

It is a Duffinian 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 5 ways as a sum of consecutive naturals, for example, 33334341 + ... + 33334390.

Almost surely, 2^1666718275 is an apocalyptic number.

1666718275 is a deficient number, since it is larger than the sum of its proper divisors (400012417).

1666718275 is an equidigital number, since it uses as much as digits as its factorization.

1666718275 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66668741 (or 66668736 counting only the distinct ones).

The product of its digits is 846720, while the sum is 49.

The square root of 1666718275 is about 40825.4611119091. The cubic root of 1666718275 is about 1185.6433390594.

The spelling of 1666718275 in words is "one billion, six hundred sixty-six million, seven hundred eighteen thousand, two hundred seventy-five".