128012791349 has 4 divisors (see below), whose sum is σ = 135542955564. Its totient is φ = 120482627136.

The previous prime is 128012791343. The next prime is 128012791381. The reversal of 128012791349 is 943197210821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 943197210821 = 222329 ⋅4242349.

It can be written as a sum of positive squares in 2 ways, for example, as 75322802500 + 52689988849 = 274450^2 + 229543^2 .

It is a cyclic number.

It is not a de Polignac number, because 128012791349 - 2²⁰ = 128011742773 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 (128012791343) 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 3 ways as a sum of consecutive naturals, for example, 3765082082 + ... + 3765082115.

It is an arithmetic number, because the mean of its divisors is an integer number (33885738891).

Almost surely, 2^128012791349 is an apocalyptic number.

It is an amenable number.

128012791349 is a deficient number, since it is larger than the sum of its proper divisors (7530164215).

128012791349 is an equidigital number, since it uses as much as digits as its factorization.

128012791349 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7530164214.

The product of its (nonzero) digits is 217728, while the sum is 47.

The spelling of 128012791349 in words is "one hundred twenty-eight billion, twelve million, seven hundred ninety-one thousand, three hundred forty-nine".