128923969849 has 16 divisors (see below), whose sum is σ = 132753816000. Its totient is φ = 125147713600.

The previous prime is 128923969777. The next prime is 128923969879. The reversal of 128923969849 is 948969329821.

It is a cyclic number.

It is not a de Polignac number, because 128923969849 - 2²³ = 128915581241 is a prime.

It is a super-2 number, since 2×128923969849² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128923969879) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8016114 + ... + 8032180.

It is an arithmetic number, because the mean of its divisors is an integer number (8297113500).

Almost surely, 2^128923969849 is an apocalyptic number.

It is an amenable number.

128923969849 is a deficient number, since it is larger than the sum of its proper divisors (3829846151).

128923969849 is a wasteful number, since it uses less digits than its factorization.

128923969849 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17720.

The product of its digits is 120932352, while the sum is 70.

The spelling of 128923969849 in words is "one hundred twenty-eight billion, nine hundred twenty-three million, nine hundred sixty-nine thousand, eight hundred forty-nine".