5991989 has 2 divisors, whose sum is σ = 5991990. Its totient is φ = 5991988.

The previous prime is 5991977. The next prime is 5991991. The reversal of 5991989 is 9891995.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4906225 + 1085764 = 2215^2 + 1042^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-5991989 is a prime.

It is a super-2 number, since 2×5991989² = 71807864352242, which contains 22 as substring.

Together with 5991991, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (5991949) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2995994 + 2995995.

It is an arithmetic number, because the mean of its divisors is an integer number (2995995).

Almost surely, 2^5991989 is an apocalyptic number.

It is an amenable number.

5991989 is a deficient number, since it is larger than the sum of its proper divisors (1).

5991989 is an equidigital number, since it uses as much as digits as its factorization.

5991989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 262440, while the sum is 50.

The square root of 5991989 is about 2447.8539580620. The cubic root of 5991989 is about 181.6311513025.

The spelling of 5991989 in words is "five million, nine hundred ninety-one thousand, nine hundred eighty-nine".