1001665 has 8 divisors (see below), whose sum is σ = 1373760. Its totient is φ = 686832.

The previous prime is 1001659. The next prime is 1001669. The reversal of 1001665 is 5661001.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1001665 - 2⁹ = 1001153 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1001669) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14275 + ... + 14344.

It is an arithmetic number, because the mean of its divisors is an integer number (171720).

2^1001665 is an apocalyptic number.

It is an amenable number.

1001665 is a deficient number, since it is larger than the sum of its proper divisors (372095).

1001665 is an equidigital number, since it uses as much as digits as its factorization.

1001665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28631.

The product of its (nonzero) digits is 180, while the sum is 19.

The square root of 1001665 is about 1000.8321537601. The cubic root of 1001665 is about 100.0554692260.

Adding to 1001665 its reverse (5661001), we get a palindrome (6662666).

The spelling of 1001665 in words is "one million, one thousand, six hundred sixty-five".