1989309 has 16 divisors (see below), whose sum is σ = 3103232. Its totient is φ = 1109808.

The previous prime is 1989307. The next prime is 1989329. The reversal of 1989309 is 9039891.

It is not a de Polignac number, because 1989309 - 2¹ = 1989307 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1989307) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 199 + ... + 2004.

It is an arithmetic number, because the mean of its divisors is an integer number (193952).

2^1989309 is an apocalyptic number.

It is an amenable number.

1989309 is a deficient number, since it is larger than the sum of its proper divisors (1113923).

1989309 is a wasteful number, since it uses less digits than its factorization.

1989309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2256.

The product of its (nonzero) digits is 17496, while the sum is 39.

The square root of 1989309 is about 1410.4286582454. The cubic root of 1989309 is about 125.7672068488.

The spelling of 1989309 in words is "one million, nine hundred eighty-nine thousand, three hundred nine".