128699999999 has 4 divisors (see below), whose sum is σ = 128701446840. Its totient is φ = 128698553160.

The previous prime is 128699999983. The next prime is 128700000017. The reversal of 128699999999 is 999999996821.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 128699999999 - 2⁴ = 128699999983 is a prime.

It is a Duffinian number.

128699999999 is a modest number, since divided by 999999 gives 128699 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128699999969) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 580592 + ... + 771029.

It is an arithmetic number, because the mean of its divisors is an integer number (32175361710).

Almost surely, 2^128699999999 is an apocalyptic number.

128699999999 is a deficient number, since it is larger than the sum of its proper divisors (1446841).

128699999999 is an equidigital number, since it uses as much as digits as its factorization.

128699999999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1446840.

The product of its digits is 4132485216, while the sum is 89.

The spelling of 128699999999 in words is "one hundred twenty-eight billion, six hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred ninety-nine".