128993547649 has 16 divisors (see below), whose sum is σ = 135086999040. Its totient is φ = 123045834240.

The previous prime is 128993547647. The next prime is 128993547667. The reversal of 128993547649 is 946745399821.

It is a cyclic number.

It is not a de Polignac number, because 128993547649 - 2¹ = 128993547647 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128993547647) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1911172 + ... + 1977514.

It is an arithmetic number, because the mean of its divisors is an integer number (8442937440).

Almost surely, 2^128993547649 is an apocalyptic number.

It is an amenable number.

128993547649 is a deficient number, since it is larger than the sum of its proper divisors (6093451391).

128993547649 is a wasteful number, since it uses less digits than its factorization.

128993547649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67440.

The product of its digits is 117573120, while the sum is 67.

The spelling of 128993547649 in words is "one hundred twenty-eight billion, nine hundred ninety-three million, five hundred forty-seven thousand, six hundred forty-nine".