2009081 has 4 divisors (see below), whose sum is σ = 2016612. Its totient is φ = 2001552.

The previous prime is 2009069. The next prime is 2009083. The reversal of 2009081 is 1809002.

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 885481 + 1123600 = 941^2 + 1060^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2009081 is a prime.

It is a super-2 number, since 2×2009081² = 8072812929122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2009083) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3350 + ... + 3903.

It is an arithmetic number, because the mean of its divisors is an integer number (504153).

2^2009081 is an apocalyptic number.

It is an amenable number.

2009081 is a deficient number, since it is larger than the sum of its proper divisors (7531).

2009081 is an equidigital number, since it uses as much as digits as its factorization.

2009081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7530.

The product of its (nonzero) digits is 144, while the sum is 20.

The square root of 2009081 is about 1417.4205445103. The cubic root of 2009081 is about 126.1825061583.

The spelling of 2009081 in words is "two million, nine thousand, eighty-one".