1005105665 has 4 divisors (see below), whose sum is σ = 1206126804. Its totient is φ = 804084528.

The previous prime is 1005105649. The next prime is 1005105701. The reversal of 1005105665 is 5665015001.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 669153424 + 335952241 = 25868^2 + 18329^2 .

It is a cyclic number.

It is not a de Polignac number, because 1005105665 - 2⁴ = 1005105649 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 100510562 + ... + 100510571.

It is an arithmetic number, because the mean of its divisors is an integer number (301531701).

Almost surely, 2^1005105665 is an apocalyptic number.

It is an amenable number.

1005105665 is a deficient number, since it is larger than the sum of its proper divisors (201021139).

1005105665 is an equidigital number, since it uses as much as digits as its factorization.

1005105665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 201021138.

The product of its (nonzero) digits is 4500, while the sum is 29.

The square root of 1005105665 is about 31703.4014736589. The cubic root of 1005105665 is about 1001.6990000972.

The spelling of 1005105665 in words is "one billion, five million, one hundred five thousand, six hundred sixty-five".