128644442115 has 32 divisors (see below), whose sum is σ = 235687159296. Its totient is φ = 58695985920.

The previous prime is 128644442039. The next prime is 128644442131. The reversal of 128644442115 is 511244446821.

It is not a de Polignac number, because 128644442115 - 2⁹ = 128644441603 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1121097 + ... + 1230506.

It is an arithmetic number, because the mean of its divisors is an integer number (7365223728).

Almost surely, 2^128644442115 is an apocalyptic number.

128644442115 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

128644442115 is a deficient number, since it is larger than the sum of its proper divisors (107042717181).

128644442115 is a wasteful number, since it uses less digits than its factorization.

128644442115 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2352139.

The product of its digits is 245760, while the sum is 42.

Adding to 128644442115 its reverse (511244446821), we get a palindrome (639888888936).

The spelling of 128644442115 in words is "one hundred twenty-eight billion, six hundred forty-four million, four hundred forty-two thousand, one hundred fifteen".