1081609 has 4 divisors (see below), whose sum is σ = 1092420. Its totient is φ = 1070800.

The previous prime is 1081583. The next prime is 1081631. The reversal of 1081609 is 9061801.

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 1040400 + 41209 = 1020^2 + 203^2 .

It is a cyclic number.

It is not a de Polignac number, because 1081609 - 2⁹ = 1081097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1081679) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5254 + ... + 5455.

It is an arithmetic number, because the mean of its divisors is an integer number (273105).

2^1081609 is an apocalyptic number.

It is an amenable number.

1081609 is a deficient number, since it is larger than the sum of its proper divisors (10811).

1081609 is a wasteful number, since it uses less digits than its factorization.

1081609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10810.

The product of its (nonzero) digits is 432, while the sum is 25.

The square root of 1081609 is about 1040.0043269141. The cubic root of 1081609 is about 102.6494824690.

The spelling of 1081609 in words is "one million, eighty-one thousand, six hundred nine".