128306929 has 2 divisors, whose sum is σ = 128306930. Its totient is φ = 128306928.

The previous prime is 128306879. The next prime is 128306947. The reversal of 128306929 is 929603821.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 84217329 + 44089600 = 9177^2 + 6640^2 .

It is a cyclic number.

It is not a de Polignac number, because 128306929 - 2¹⁵ = 128274161 is a prime.

It is a super-2 number, since 2×128306929² = 32925336058822082, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 128306891 and 128306900.

It is not a weakly prime, because it can be changed into another prime (128306989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64153464 + 64153465.

It is an arithmetic number, because the mean of its divisors is an integer number (64153465).

Almost surely, 2^128306929 is an apocalyptic number.

It is an amenable number.

128306929 is a deficient number, since it is larger than the sum of its proper divisors (1).

128306929 is an equidigital number, since it uses as much as digits as its factorization.

128306929 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 46656, while the sum is 40.

The square root of 128306929 is about 11327.2648507925. The cubic root of 128306929 is about 504.3709174860.

The spelling of 128306929 in words is "one hundred twenty-eight million, three hundred six thousand, nine hundred twenty-nine".