128240979745 has 4 divisors (see below), whose sum is σ = 153889175700. Its totient is φ = 102592783792.

The previous prime is 128240979719. The next prime is 128240979761. The reversal of 128240979745 is 547979042821.

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

It can be written as a sum of positive squares in 2 ways, for example, as 99526999441 + 28713980304 = 315479^2 + 169452^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128240979745 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 128240979745.

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 3 ways as a sum of consecutive naturals, for example, 12824097970 + ... + 12824097979.

It is an arithmetic number, because the mean of its divisors is an integer number (38472293925).

Almost surely, 2^128240979745 is an apocalyptic number.

It is an amenable number.

128240979745 is a deficient number, since it is larger than the sum of its proper divisors (25648195955).

128240979745 is an equidigital number, since it uses as much as digits as its factorization.

128240979745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25648195954.

The product of its (nonzero) digits is 10160640, while the sum is 58.

The spelling of 128240979745 in words is "one hundred twenty-eight billion, two hundred forty million, nine hundred seventy-nine thousand, seven hundred forty-five".