1809398 has 8 divisors (see below), whose sum is σ = 2723760. Its totient is φ = 901480.

The previous prime is 1809391. The next prime is 1809403. The reversal of 1809398 is 8939081.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×1809398² = 6547842244808, which contains 22 as substring.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1809391) 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, 833 + ... + 2076.

It is an arithmetic number, because the mean of its divisors is an integer number (340470).

2^1809398 is an apocalyptic number.

1809398 is a deficient number, since it is larger than the sum of its proper divisors (914362).

1809398 is a wasteful number, since it uses less digits than its factorization.

1809398 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3222.

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

The square root of 1809398 is about 1345.1386545632. The cubic root of 1809398 is about 121.8553782130.

The spelling of 1809398 in words is "one million, eight hundred nine thousand, three hundred ninety-eight".