308989 has 2 divisors, whose sum is σ = 308990.
Its totient is φ = 308988.
The previous prime is 308951. The next prime is 308999. The reversal of 308989 is 989803.
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 209764 + 99225 = 458^2 + 315^2
It is an emirp because it is prime and its reverse (989803) is a distict prime.
It is a cyclic number.
It is not a de Polignac number, because 308989 - 211 = 306941 is a prime.
It is an Ulam number.
308989 is a lucky number.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (308929) 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 as a sum of consecutive naturals, namely, 154494 + 154495.
It is an arithmetic number, because the mean of its divisors is an integer number (154495).
2308989 is an apocalyptic number.
It is an amenable number.
308989 is a deficient number, since it is larger than the sum of its proper divisors (1).
308989 is an equidigital number, since it uses as much as digits as its factorization.
308989 is an odious number, because the sum of its binary digits is odd.
The product of its (nonzero) digits is 15552, while the sum is 37.
The square root of 308989 is about 555.8677900364.
The cubic root of 308989 is about 67.6053407776.
The spelling of 308989 in words is "three hundred eight thousand, nine hundred eighty-nine".