1809138 has 16 divisors (see below), whose sum is σ = 3678336. Its totient is φ = 593040.

The previous prime is 1809133. The next prime is 1809149. The reversal of 1809138 is 8319081.

It is not an unprimeable number, because it can be changed into a prime (1809133) 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 7 ways as a sum of consecutive naturals, for example, 2106 + ... + 2837.

It is an arithmetic number, because the mean of its divisors is an integer number (229896).

2^1809138 is an apocalyptic number.

1809138 is an abundant number, since it is smaller than the sum of its proper divisors (1869198).

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

1809138 is a wasteful number, since it uses less digits than its factorization.

1809138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5009.

The product of its (nonzero) digits is 1728, while the sum is 30.

The square root of 1809138 is about 1345.0420067790. The cubic root of 1809138 is about 121.8495412963.

The spelling of 1809138 in words is "one million, eight hundred nine thousand, one hundred thirty-eight".