128406605 has 4 divisors (see below), whose sum is σ = 154087932. Its totient is φ = 102725280.

The previous prime is 128406599. The next prime is 128406611. The reversal of 128406605 is 506604821.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (128406599) and next prime (128406611).

It can be written as a sum of positive squares in 2 ways, for example, as 97259044 + 31147561 = 9862^2 + 5581^2 .

It is not a de Polignac number, because 128406605 - 2⁴ = 128406589 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12840656 + ... + 12840665.

It is an arithmetic number, because the mean of its divisors is an integer number (38521983).

Almost surely, 2^128406605 is an apocalyptic number.

It is an amenable number.

128406605 is a deficient number, since it is larger than the sum of its proper divisors (25681327).

128406605 is an equidigital number, since it uses as much as digits as its factorization.

128406605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25681326.

The product of its (nonzero) digits is 11520, while the sum is 32.

The square root of 128406605 is about 11331.6638231109. The cubic root of 128406605 is about 504.5014915272.

The spelling of 128406605 in words is "one hundred twenty-eight million, four hundred six thousand, six hundred five".