128126523578 has 4 divisors (see below), whose sum is σ = 192189785370. Its totient is φ = 64063261788.

The previous prime is 128126523529. The next prime is 128126523583. The reversal of 128126523578 is 875325621821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 875325621821 = 7 ⋅125046517403.

It can be written as a sum of positive squares in only one way, i.e., 116255767369 + 11870756209 = 340963^2 + 108953^2 .

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32031630893 + ... + 32031630896.

Almost surely, 2^128126523578 is an apocalyptic number.

128126523578 is a deficient number, since it is larger than the sum of its proper divisors (64063261792).

128126523578 is an equidigital number, since it uses as much as digits as its factorization.

128126523578 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64063261791.

The product of its digits is 1612800, while the sum is 50.

The spelling of 128126523578 in words is "one hundred twenty-eight billion, one hundred twenty-six million, five hundred twenty-three thousand, five hundred seventy-eight".