1665535273 has 4 divisors (see below), whose sum is σ = 1668526020. Its totient is φ = 1662544528.

The previous prime is 1665535247. The next prime is 1665535283. The reversal of 1665535273 is 3725355661.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3725355661 = 5237 ⋅711353.

It can be written as a sum of positive squares in 2 ways, for example, as 295943209 + 1369592064 = 17203^2 + 37008^2 .

It is a cyclic number.

It is not a de Polignac number, because 1665535273 - 2⁵ = 1665535241 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1665535283) 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 in 3 ways as a sum of consecutive naturals, for example, 1494538 + ... + 1495651.

It is an arithmetic number, because the mean of its divisors is an integer number (417131505).

Almost surely, 2^1665535273 is an apocalyptic number.

It is an amenable number.

1665535273 is a deficient number, since it is larger than the sum of its proper divisors (2990747).

1665535273 is an equidigital number, since it uses as much as digits as its factorization.

1665535273 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2990746.

The product of its digits is 567000, while the sum is 43.

The square root of 1665535273 is about 40810.9700080750. The cubic root of 1665535273 is about 1185.3627576632.

The spelling of 1665535273 in words is "one billion, six hundred sixty-five million, five hundred thirty-five thousand, two hundred seventy-three".