129393989 has 2 divisors, whose sum is σ = 129393990. Its totient is φ = 129393988.

The previous prime is 129393983. The next prime is 129394003. The reversal of 129393989 is 989393921.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 129390625 + 3364 = 11375^2 + 58^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-129393989 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 129393989.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (129393983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64696994 + 64696995.

It is an arithmetic number, because the mean of its divisors is an integer number (64696995).

Almost surely, 2^129393989 is an apocalyptic number.

It is an amenable number.

129393989 is a deficient number, since it is larger than the sum of its proper divisors (1).

129393989 is an equidigital number, since it uses as much as digits as its factorization.

129393989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 944784, while the sum is 53.

The square root of 129393989 is about 11375.1478671708. The cubic root of 129393989 is about 505.7913143733.

The spelling of 129393989 in words is "one hundred twenty-nine million, three hundred ninety-three thousand, nine hundred eighty-nine".