1813689 has 12 divisors (see below), whose sum is σ = 2710500. Its totient is φ = 1167264.

The previous prime is 1813681. The next prime is 1813699. The reversal of 1813689 is 9863181.

It can be written as a sum of positive squares in 2 ways, for example, as 1299600 + 514089 = 1140^2 + 717^2 .

It is not a de Polignac number, because 1813689 - 2³ = 1813681 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1813681) 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 11 ways as a sum of consecutive naturals, for example, 3214 + ... + 3735.

It is an arithmetic number, because the mean of its divisors is an integer number (225875).

2^1813689 is an apocalyptic number.

It is an amenable number.

1813689 is a deficient number, since it is larger than the sum of its proper divisors (896811).

1813689 is a wasteful number, since it uses less digits than its factorization.

1813689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6984 (or 6981 counting only the distinct ones).

The product of its digits is 10368, while the sum is 36.

The square root of 1813689 is about 1346.7327129019. The cubic root of 1813689 is about 121.9516291268.

It can be divided in two parts, 18136 and 89, that added together give a square (18225 = 135²).

The spelling of 1813689 in words is "one million, eight hundred thirteen thousand, six hundred eighty-nine".