128261695 has 4 divisors (see below), whose sum is σ = 153914040. Its totient is φ = 102609352.

The previous prime is 128261659. The next prime is 128261701. The reversal of 128261695 is 596162821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 596162821 = 61 ⋅9773161.

It is a cyclic number.

It is not a de Polignac number, because 128261695 - 2²¹ = 126164543 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12826165 + ... + 12826174.

It is an arithmetic number, because the mean of its divisors is an integer number (38478510).

Almost surely, 2^128261695 is an apocalyptic number.

128261695 is a deficient number, since it is larger than the sum of its proper divisors (25652345).

128261695 is an equidigital number, since it uses as much as digits as its factorization.

128261695 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25652344.

The product of its digits is 51840, while the sum is 40.

The square root of 128261695 is about 11325.2679879992. The cubic root of 128261695 is about 504.3116393268.

The spelling of 128261695 in words is "one hundred twenty-eight million, two hundred sixty-one thousand, six hundred ninety-five".