2019989 has 4 divisors (see below), whose sum is σ = 2058156. Its totient is φ = 1981824.

The previous prime is 2019977. The next prime is 2020001. The reversal of 2019989 is 9899102.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9899102 = 2 ⋅4949551.

It is an interprime number because it is at equal distance from previous prime (2019977) and next prime (2020001).

It can be written as a sum of positive squares in 2 ways, for example, as 1311025 + 708964 = 1145^2 + 842^2 .

It is a cyclic number.

It is not a de Polignac number, because 2019989 - 2⁴ = 2019973 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 (2019959) 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, 19004 + ... + 19109.

It is an arithmetic number, because the mean of its divisors is an integer number (514539).

2^2019989 is an apocalyptic number.

It is an amenable number.

2019989 is a deficient number, since it is larger than the sum of its proper divisors (38167).

2019989 is an equidigital number, since it uses as much as digits as its factorization.

2019989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38166.

The product of its (nonzero) digits is 11664, while the sum is 38.

The square root of 2019989 is about 1421.2631705634. The cubic root of 2019989 is about 126.4104570276.

The spelling of 2019989 in words is "two million, nineteen thousand, nine hundred eighty-nine".