128866457 has 2 divisors, whose sum is σ = 128866458. Its totient is φ = 128866456.

The previous prime is 128866357. The next prime is 128866469. The reversal of 128866457 is 754668821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 85451536 + 43414921 = 9244^2 + 6589^2 .

It is a cyclic number.

It is not a de Polignac number, because 128866457 - 2⁸ = 128866201 is a prime.

It is not a weakly prime, because it can be changed into another prime (128866357) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64433228 + 64433229.

It is an arithmetic number, because the mean of its divisors is an integer number (64433229).

Almost surely, 2^128866457 is an apocalyptic number.

It is an amenable number.

128866457 is a deficient number, since it is larger than the sum of its proper divisors (1).

128866457 is an equidigital number, since it uses as much as digits as its factorization.

128866457 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 645120, while the sum is 47.

The square root of 128866457 is about 11351.9362665582. The cubic root of 128866457 is about 505.1030172478.

The spelling of 128866457 in words is "one hundred twenty-eight million, eight hundred sixty-six thousand, four hundred fifty-seven".