1804861 has 4 divisors (see below), whose sum is σ = 1848924. Its totient is φ = 1760800.

The previous prime is 1804841. The next prime is 1804871. The reversal of 1804861 is 1684081.

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 352836 + 1452025 = 594^2 + 1205^2 .

It is a cyclic number.

It is not a de Polignac number, because 1804861 - 2⁹ = 1804349 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1804801) 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, 21970 + ... + 22051.

It is an arithmetic number, because the mean of its divisors is an integer number (462231).

2^1804861 is an apocalyptic number.

It is an amenable number.

1804861 is a deficient number, since it is larger than the sum of its proper divisors (44063).

1804861 is an equidigital number, since it uses as much as digits as its factorization.

1804861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44062.

The product of its (nonzero) digits is 1536, while the sum is 28.

The square root of 1804861 is about 1343.4511528150. The cubic root of 1804861 is about 121.7534436495.

It can be divided in two parts, 180 and 4861, that added together give a square (5041 = 71²).

The spelling of 1804861 in words is "one million, eight hundred four thousand, eight hundred sixty-one".