1808819 has 16 divisors (see below), whose sum is σ = 2042880. Its totient is φ = 1594080.

The previous prime is 1808813. The next prime is 1808831. The reversal of 1808819 is 9188081.

It is a cyclic number.

It is not a de Polignac number, because 1808819 - 2⁴ = 1808803 is a prime.

It is a super-2 number, since 2×1808819² = 6543652349522, which contains 22 as substring.

It is a Smith number, since the sum of its digits (35) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (1808813) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21752 + ... + 21834.

It is an arithmetic number, because the mean of its divisors is an integer number (127680).

2^1808819 is an apocalyptic number.

1808819 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

1808819 is a deficient number, since it is larger than the sum of its proper divisors (234061).

1808819 is a wasteful number, since it uses less digits than its factorization.

1808819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 170.

The product of its (nonzero) digits is 4608, while the sum is 35.

The square root of 1808819 is about 1344.9234178941. The cubic root of 1808819 is about 121.8423790845.

The spelling of 1808819 in words is "one million, eight hundred eight thousand, eight hundred nineteen".