1665053809 has 16 divisors (see below), whose sum is σ = 1786060800. Its totient is φ = 1547496144.

The previous prime is 1665053759. The next prime is 1665053837. The reversal of 1665053809 is 9083505661.

It is a cyclic number.

It is not a de Polignac number, because 1665053809 - 2⁷ = 1665053681 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1665053839) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 679224 + ... + 681670.

It is an arithmetic number, because the mean of its divisors is an integer number (111628800).

Almost surely, 2^1665053809 is an apocalyptic number.

1665053809 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

1665053809 is a deficient number, since it is larger than the sum of its proper divisors (121006991).

1665053809 is a wasteful number, since it uses less digits than its factorization.

1665053809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3132.

The product of its (nonzero) digits is 194400, while the sum is 43.

The square root of 1665053809 is about 40805.0708736059. The cubic root of 1665053809 is about 1185.2485272202.

The spelling of 1665053809 in words is "one billion, six hundred sixty-five million, fifty-three thousand, eight hundred nine".