128899 has 4 divisors (see below), whose sum is σ = 130536. Its totient is φ = 127264.

The previous prime is 128879. The next prime is 128903. The reversal of 128899 is 998821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 998821 = 23 ⋅43427.

It is a cyclic number.

It is not a de Polignac number, because 128899 - 2¹¹ = 126851 is a prime.

It is a super-2 number, since 2×128899² = 33229904402, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 694 + ... + 859.

It is an arithmetic number, because the mean of its divisors is an integer number (32634).

2¹²⁸⁸⁹⁹ is an apocalyptic number.

128899 is a deficient number, since it is larger than the sum of its proper divisors (1637).

128899 is an equidigital number, since it uses as much as digits as its factorization.

128899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1636.

The product of its digits is 10368, while the sum is 37.

The square root of 128899 is about 359.0250687626. The cubic root of 128899 is about 50.5145532020.

It can be divided in two parts, 12 and 8899, that added together give a triangular number (8911 = T₁₃₃).

The spelling of 128899 in words is "one hundred twenty-eight thousand, eight hundred ninety-nine".