989971 has 2 divisors, whose sum is σ = 989972. Its totient is φ = 989970.

The previous prime is 989959. The next prime is 989977. The reversal of 989971 is 179989.

It is a strong prime.

It is an emirp because it is prime and its reverse (179989) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 989971 - 2⁵ = 989939 is a prime.

It is not a weakly prime, because it can be changed into another prime (989977) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 494985 + 494986.

It is an arithmetic number, because the mean of its divisors is an integer number (494986).

2⁹⁸⁹⁹⁷¹ is an apocalyptic number.

989971 is a deficient number, since it is larger than the sum of its proper divisors (1).

989971 is an equidigital number, since it uses as much as digits as its factorization.

989971 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 40824, while the sum is 43.

The square root of 989971 is about 994.9728639516. The cubic root of 989971 is about 99.6645761665.

The spelling of 989971 in words is "nine hundred eighty-nine thousand, nine hundred seventy-one".