12128345 has 4 divisors (see below), whose sum is σ = 14554020. Its totient is φ = 9702672.

The previous prime is 12128339. The next prime is 12128357. The reversal of 12128345 is 54382121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 54382121 = 353 ⋅154057.

It can be written as a sum of positive squares in 2 ways, for example, as 2343961 + 9784384 = 1531^2 + 3128^2 .

It is a cyclic number.

It is not a de Polignac number, because 12128345 - 2⁴ = 12128329 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1212830 + ... + 1212839.

It is an arithmetic number, because the mean of its divisors is an integer number (3638505).

Almost surely, 2^12128345 is an apocalyptic number.

It is an amenable number.

12128345 is a deficient number, since it is larger than the sum of its proper divisors (2425675).

12128345 is an equidigital number, since it uses as much as digits as its factorization.

12128345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2425674.

The product of its digits is 1920, while the sum is 26.

The square root of 12128345 is about 3482.5773501819. The cubic root of 12128345 is about 229.7561688184.

The spelling of 12128345 in words is "twelve million, one hundred twenty-eight thousand, three hundred forty-five".