1808861 has 4 divisors (see below), whose sum is σ = 1823232. Its totient is φ = 1794492.

The previous prime is 1808843. The next prime is 1808869. The reversal of 1808861 is 1688081.

It is a happy number.

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 1808861 - 2¹⁰ = 1807837 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1808869) 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, 6995 + ... + 7248.

It is an arithmetic number, because the mean of its divisors is an integer number (455808).

2^1808861 is an apocalyptic number.

It is an amenable number.

1808861 is a deficient number, since it is larger than the sum of its proper divisors (14371).

1808861 is a wasteful number, since it uses less digits than its factorization.

1808861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14370.

The product of its (nonzero) digits is 3072, while the sum is 32.

The square root of 1808861 is about 1344.9390320754. The cubic root of 1808861 is about 121.8433221198.

The spelling of 1808861 in words is "one million, eight hundred eight thousand, eight hundred sixty-one".