128675681 has 4 divisors (see below), whose sum is σ = 128871600. Its totient is φ = 128479764.

The previous prime is 128675653. The next prime is 128675719. The reversal of 128675681 is 186576821.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 186576821 = 59 ⋅3162319.

It is a cyclic number.

It is not a de Polignac number, because 128675681 - 2¹⁰ = 128674657 is a prime.

It is a super-2 number, since 2×128675681² = 33114861761627522, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (128678681) by changing a digit.

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, 96971 + ... + 98288.

It is an arithmetic number, because the mean of its divisors is an integer number (32217900).

Almost surely, 2^128675681 is an apocalyptic number.

It is an amenable number.

128675681 is a deficient number, since it is larger than the sum of its proper divisors (195919).

128675681 is an equidigital number, since it uses as much as digits as its factorization.

128675681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195918.

The product of its digits is 161280, while the sum is 44.

The square root of 128675681 is about 11343.5303587552. The cubic root of 128675681 is about 504.8536399045.

It can be divided in two parts, 1286 and 75681, that added together give a palindrome (76967).

The spelling of 128675681 in words is "one hundred twenty-eight million, six hundred seventy-five thousand, six hundred eighty-one".