128128799 has 8 divisors (see below), whose sum is σ = 135734640. Its totient is φ = 120609216.

The previous prime is 128128789. The next prime is 128128811. The reversal of 128128799 is 997821821.

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

It is a cyclic number.

It is not a de Polignac number, because 128128799 - 2⁴ = 128128783 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128128739) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18494 + ... + 24459.

It is an arithmetic number, because the mean of its divisors is an integer number (16966830).

Almost surely, 2^128128799 is an apocalyptic number.

128128799 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

128128799 is a deficient number, since it is larger than the sum of its proper divisors (7605841).

128128799 is a wasteful number, since it uses less digits than its factorization.

128128799 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43129.

The product of its digits is 145152, while the sum is 47.

The square root of 128128799 is about 11319.3992331749. The cubic root of 128128799 is about 504.1374013870.

The spelling of 128128799 in words is "one hundred twenty-eight million, one hundred twenty-eight thousand, seven hundred ninety-nine".