128142778915 has 8 divisors (see below), whose sum is σ = 161864562960. Its totient is φ = 97118737632.

The previous prime is 128142778867. The next prime is 128142778921. The reversal of 128142778915 is 519877241821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128142778915 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 674435584 + ... + 674435773.

It is an arithmetic number, because the mean of its divisors is an integer number (20233070370).

Almost surely, 2^128142778915 is an apocalyptic number.

128142778915 is a deficient number, since it is larger than the sum of its proper divisors (33721784045).

128142778915 is a wasteful number, since it uses less digits than its factorization.

128142778915 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1348871381.

The product of its digits is 2257920, while the sum is 55.

The spelling of 128142778915 in words is "one hundred twenty-eight billion, one hundred forty-two million, seven hundred seventy-eight thousand, nine hundred fifteen".