2021989 has 8 divisors (see below), whose sum is σ = 2106720. Its totient is φ = 1939056.

The previous prime is 2021959. The next prime is 2022011. The reversal of 2021989 is 9891202.

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 2021989 - 2¹⁹ = 1497701 is a prime.

It is a super-2 number, since 2×2021989² = 8176879032242, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2021989.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2021959) 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 7 ways as a sum of consecutive naturals, for example, 2139 + ... + 2935.

It is an arithmetic number, because the mean of its divisors is an integer number (263340).

2^2021989 is an apocalyptic number.

It is an amenable number.

2021989 is a deficient number, since it is larger than the sum of its proper divisors (84731).

2021989 is an equidigital number, since it uses as much as digits as its factorization.

2021989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 899.

The product of its (nonzero) digits is 2592, while the sum is 31.

The square root of 2021989 is about 1421.9665959508. The cubic root of 2021989 is about 126.4521631161.

The spelling of 2021989 in words is "two million, twenty-one thousand, nine hundred eighty-nine".