320129989 has 2 divisors, whose sum is σ = 320129990. Its totient is φ = 320129988.

The previous prime is 320129987. The next prime is 320130007. The reversal of 320129989 is 989921023.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 220968225 + 99161764 = 14865^2 + 9958^2 .

It is a cyclic number.

It is not a de Polignac number, because 320129989 - 2¹ = 320129987 is a prime.

Together with 320129987, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (320129987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160064994 + 160064995.

It is an arithmetic number, because the mean of its divisors is an integer number (160064995).

Almost surely, 2^320129989 is an apocalyptic number.

It is an amenable number.

320129989 is a deficient number, since it is larger than the sum of its proper divisors (1).

320129989 is an equidigital number, since it uses as much as digits as its factorization.

320129989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 69984, while the sum is 43.

The square root of 320129989 is about 17892.1767541012. The cubic root of 320129989 is about 684.0829819926.

The spelling of 320129989 in words is "three hundred twenty million, one hundred twenty-nine thousand, nine hundred eighty-nine".