1808081 has 4 divisors (see below), whose sum is σ = 1972464. Its totient is φ = 1643700.

The previous prime is 1808077. The next prime is 1808083.

1808081 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1808081 - 2² = 1808077 is a prime.

It is a super-2 number, since 2×1808081² = 6538313805122, which contains 22 as substring.

1808081 is a strobogrammatic number because it is the same when read upside-down.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1808081.

It is not an unprimeable number, because it can be changed into a prime (1808083) 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, 82175 + ... + 82196.

It is an arithmetic number, because the mean of its divisors is an integer number (493116).

2^1808081 is an apocalyptic number.

1808081 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1808081 is a deficient number, since it is larger than the sum of its proper divisors (164383).

1808081 is a wasteful number, since it uses less digits than its factorization.

1808081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164382.

The product of its (nonzero) digits is 512, while the sum is 26.

The square root of 1808081 is about 1344.6490248388. The cubic root of 1808081 is about 121.8258062254.

The spelling of 1808081 in words is "one million, eight hundred eight thousand, eighty-one".