1091665 has 8 divisors (see below), whose sum is σ = 1352448. Its totient is φ = 845040.

The previous prime is 1091663. The next prime is 1091681. The reversal of 1091665 is 5661901.

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

It is not a de Polignac number, because 1091665 - 2¹ = 1091663 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1091663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3367 + ... + 3676.

It is an arithmetic number, because the mean of its divisors is an integer number (169056).

2^1091665 is an apocalyptic number.

It is an amenable number.

1091665 is a deficient number, since it is larger than the sum of its proper divisors (260783).

1091665 is an equidigital number, since it uses as much as digits as its factorization.

1091665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7079.

The product of its (nonzero) digits is 1620, while the sum is 28.

The square root of 1091665 is about 1044.8277369978. The cubic root of 1091665 is about 102.9666212891.

The spelling of 1091665 in words is "one million, ninety-one thousand, six hundred sixty-five".