1665290265 has 16 divisors (see below), whose sum is σ = 2736477888. Its totient is φ = 864150336.

The previous prime is 1665290257. The next prime is 1665290269. The reversal of 1665290265 is 5620925661.

It is not a de Polignac number, because 1665290265 - 2³ = 1665290257 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1665290269) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1499707 + ... + 1500816.

It is an arithmetic number, because the mean of its divisors is an integer number (171029868).

Almost surely, 2^1665290265 is an apocalyptic number.

1665290265 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1665290265 is a deficient number, since it is larger than the sum of its proper divisors (1071187623).

1665290265 is a wasteful number, since it uses less digits than its factorization.

1665290265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3000568.

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

The square root of 1665290265 is about 40807.9681557413. The cubic root of 1665290265 is about 1185.3046306844.

The spelling of 1665290265 in words is "one billion, six hundred sixty-five million, two hundred ninety thousand, two hundred sixty-five".