1665669671 has 2 divisors, whose sum is σ = 1665669672. Its totient is φ = 1665669670.

The previous prime is 1665669619. The next prime is 1665669703. The reversal of 1665669671 is 1769665661.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1665669671 - 2¹⁰ = 1665668647 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1665669611) by changing a digit.

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 as a sum of consecutive naturals, namely, 832834835 + 832834836.

It is an arithmetic number, because the mean of its divisors is an integer number (832834836).

Almost surely, 2^1665669671 is an apocalyptic number.

1665669671 is a deficient number, since it is larger than the sum of its proper divisors (1).

1665669671 is an equidigital number, since it uses as much as digits as its factorization.

1665669671 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2449440, while the sum is 53.

The square root of 1665669671 is about 40812.6165664492. The cubic root of 1665669671 is about 1185.3946405262.

The spelling of 1665669671 in words is "one billion, six hundred sixty-five million, six hundred sixty-nine thousand, six hundred seventy-one".