1809040 has 20 divisors (see below), whose sum is σ = 4206204. Its totient is φ = 723584.

The previous prime is 1809029. The next prime is 1809079. The reversal of 1809040 is 409081.

It can be written as a sum of positive squares in 2 ways, for example, as 719104 + 1089936 = 848^2 + 1044^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11227 + ... + 11386.

2^1809040 is an apocalyptic number.

1809040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1809040 is an abundant number, since it is smaller than the sum of its proper divisors (2397164).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1809040 is a wasteful number, since it uses less digits than its factorization.

1809040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22626 (or 22620 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 22.

The square root of 1809040 is about 1345.0055761966. The cubic root of 1809040 is about 121.8473410826.

The spelling of 1809040 in words is "one million, eight hundred nine thousand, forty".