128686123 has 2 divisors, whose sum is σ = 128686124. Its totient is φ = 128686122.

The previous prime is 128686099. The next prime is 128686153. The reversal of 128686123 is 321686821.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 128686123 - 2⁹ = 128685611 is a prime.

It is a super-2 number, since 2×128686123² = 33120236505542258, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (128686153) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64343061 + 64343062.

It is an arithmetic number, because the mean of its divisors is an integer number (64343062).

Almost surely, 2^128686123 is an apocalyptic number.

128686123 is a deficient number, since it is larger than the sum of its proper divisors (1).

128686123 is an equidigital number, since it uses as much as digits as its factorization.

128686123 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27648, while the sum is 37.

The square root of 128686123 is about 11343.9906117733. The cubic root of 128686123 is about 504.8672957848.

The spelling of 128686123 in words is "one hundred twenty-eight million, six hundred eighty-six thousand, one hundred twenty-three".