128181847665 has 32 divisors (see below), whose sum is σ = 219424348800. Its totient is φ = 63703825920.

The previous prime is 128181847637. The next prime is 128181847667. The reversal of 128181847665 is 566748181821.

It is not a de Polignac number, because 128181847665 - 2⁶ = 128181847601 is a prime.

It is a Smith number, since the sum of its digits (57) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Harshad number since it is a multiple of its sum of digits (57).

It is not an unprimeable number, because it can be changed into a prime (128181847667) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3669180 + ... + 3703949.

It is an arithmetic number, because the mean of its divisors is an integer number (6857010900).

Almost surely, 2^128181847665 is an apocalyptic number.

128181847665 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

128181847665 is a deficient number, since it is larger than the sum of its proper divisors (91242501135).

128181847665 is a wasteful number, since it uses less digits than its factorization.

128181847665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7373217.

The product of its digits is 5160960, while the sum is 57.

The spelling of 128181847665 in words is "one hundred twenty-eight billion, one hundred eighty-one million, eight hundred forty-seven thousand, six hundred sixty-five".