1812889 has 8 divisors (see below), whose sum is σ = 2005640. Its totient is φ = 1627776.

The previous prime is 1812871. The next prime is 1812907. The reversal of 1812889 is 9882181.

It is an interprime number because it is at equal distance from previous prime (1812871) and next prime (1812907).

It can be written as a sum of positive squares in 4 ways, for example, as 585225 + 1227664 = 765^2 + 1108^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 1812889 - 2¹⁷ = 1681817 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is not an unprimeable number, because it can be changed into a prime (1812869) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1404 + ... + 2365.

It is an arithmetic number, because the mean of its divisors is an integer number (250705).

2^1812889 is an apocalyptic number.

It is an amenable number.

1812889 is a deficient number, since it is larger than the sum of its proper divisors (192751).

1812889 is a wasteful number, since it uses less digits than its factorization.

1812889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3819.

The product of its digits is 9216, while the sum is 37.

The square root of 1812889 is about 1346.4356650059. The cubic root of 1812889 is about 121.9336959436.

It can be divided in two parts, 1812 and 889, that added together give a triangular number (2701 = T₇₃).

The spelling of 1812889 in words is "one million, eight hundred twelve thousand, eight hundred eighty-nine".