1899989 has 8 divisors (see below), whose sum is σ = 2338560. Its totient is φ = 1503216.

The previous prime is 1899983. The next prime is 1900009. The reversal of 1899989 is 9899981.

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

It is not a de Polignac number, because 1899989 - 2¹² = 1895893 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1899989.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1899983) 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, 10349 + ... + 10530.

It is an arithmetic number, because the mean of its divisors is an integer number (292320).

2^1899989 is an apocalyptic number.

It is an amenable number.

1899989 is a deficient number, since it is larger than the sum of its proper divisors (438571).

1899989 is a wasteful number, since it uses less digits than its factorization.

1899989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20899.

The product of its digits is 419904, while the sum is 53.

The square root of 1899989 is about 1378.4008850839. The cubic root of 1899989 is about 123.8559939418.

The spelling of 1899989 in words is "one million, eight hundred ninety-nine thousand, nine hundred eighty-nine".