1803989 has 12 divisors (see below), whose sum is σ = 2101932. Its totient is φ = 1541760.

The previous prime is 1803973. The next prime is 1804007. The reversal of 1803989 is 9893081.

1803989 = 57² + 58² + ... + 177².

It can be written as a sum of positive squares in 2 ways, for example, as 1464100 + 339889 = 1210^2 + 583^2 .

It is not a de Polignac number, because 1803989 - 2⁴ = 1803973 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 (1803089) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1619 + ... + 2495.

It is an arithmetic number, because the mean of its divisors is an integer number (175161).

2^1803989 is an apocalyptic number.

It is an amenable number.

1803989 is a deficient number, since it is larger than the sum of its proper divisors (297943).

1803989 is a wasteful number, since it uses less digits than its factorization.

1803989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 916 (or 905 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 38.

The square root of 1803989 is about 1343.1265763136. The cubic root of 1803989 is about 121.7338325168.

The spelling of 1803989 in words is "one million, eight hundred three thousand, nine hundred eighty-nine".