8021989 has 2 divisors, whose sum is σ = 8021990. Its totient is φ = 8021988.

The previous prime is 8021969. The next prime is 8021999. The reversal of 8021989 is 9891208.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5919489 + 2102500 = 2433^2 + 1450^2 .

It is a cyclic number.

It is not a de Polignac number, because 8021989 - 2¹⁵ = 7989221 is a prime.

It is a super-2 number, since 2×8021989² = 128704615032242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8021939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4010994 + 4010995.

It is an arithmetic number, because the mean of its divisors is an integer number (4010995).

Almost surely, 2^8021989 is an apocalyptic number.

It is an amenable number.

8021989 is a deficient number, since it is larger than the sum of its proper divisors (1).

8021989 is an equidigital number, since it uses as much as digits as its factorization.

8021989 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10368, while the sum is 37.

The square root of 8021989 is about 2832.3116000892. The cubic root of 8021989 is about 200.1830740350.

It can be divided in two parts, 80219 and 89, that added together give a palindrome (80308).

The spelling of 8021989 in words is "eight million, twenty-one thousand, nine hundred eighty-nine".