128663405 has 8 divisors (see below), whose sum is σ = 166272792. Its totient is φ = 95012928.

The previous prime is 128663399. The next prime is 128663411. The reversal of 128663405 is 504366821.

It is an interprime number because it is at equal distance from previous prime (128663399) and next prime (128663411).

It can be written as a sum of positive squares in 4 ways, for example, as 27741289 + 100922116 = 5267^2 + 10046^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 128663405 - 2⁴ = 128663389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 989654 + ... + 989783.

It is an arithmetic number, because the mean of its divisors is an integer number (20784099).

Almost surely, 2^128663405 is an apocalyptic number.

It is an amenable number.

128663405 is a deficient number, since it is larger than the sum of its proper divisors (37609387).

128663405 is a wasteful number, since it uses less digits than its factorization.

128663405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1979455.

The product of its (nonzero) digits is 34560, while the sum is 35.

The square root of 128663405 is about 11342.9892444629. The cubic root of 128663405 is about 504.8375846034.

The spelling of 128663405 in words is "one hundred twenty-eight million, six hundred sixty-three thousand, four hundred five".