128366993 has 2 divisors, whose sum is σ = 128366994. Its totient is φ = 128366992.

The previous prime is 128366981. The next prime is 128366999. The reversal of 128366993 is 399663821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 102070609 + 26296384 = 10103^2 + 5128^2 .

It is a cyclic number.

It is not a de Polignac number, because 128366993 - 2⁴ = 128366977 is a prime.

It is not a weakly prime, because it can be changed into another prime (128366999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64183496 + 64183497.

It is an arithmetic number, because the mean of its divisors is an integer number (64183497).

Almost surely, 2^128366993 is an apocalyptic number.

It is an amenable number.

128366993 is a deficient number, since it is larger than the sum of its proper divisors (1).

128366993 is an equidigital number, since it uses as much as digits as its factorization.

128366993 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 419904, while the sum is 47.

The square root of 128366993 is about 11329.9158425824. The cubic root of 128366993 is about 504.4496085045.

The spelling of 128366993 in words is "one hundred twenty-eight million, three hundred sixty-six thousand, nine hundred ninety-three".