128985793847 has 4 divisors (see below), whose sum is σ = 130539839640. Its totient is φ = 127431748056.

The previous prime is 128985793843. The next prime is 128985793861. The reversal of 128985793847 is 748397589821.

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 128985793847 - 2² = 128985793843 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 (128985793843) 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, 777022772 + ... + 777022937.

It is an arithmetic number, because the mean of its divisors is an integer number (32634959910).

Almost surely, 2^128985793847 is an apocalyptic number.

128985793847 is a deficient number, since it is larger than the sum of its proper divisors (1554045793).

128985793847 is an equidigital number, since it uses as much as digits as its factorization.

128985793847 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1554045792.

The product of its digits is 243855360, while the sum is 71.

The spelling of 128985793847 in words is "one hundred twenty-eight billion, nine hundred eighty-five million, seven hundred ninety-three thousand, eight hundred forty-seven".