128393449 has 4 divisors (see below), whose sum is σ = 129255300. Its totient is φ = 127531600.

The previous prime is 128393437. The next prime is 128393467. The reversal of 128393449 is 944393821.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 77528025 + 50865424 = 8805^2 + 7132^2 .

It is a cyclic number.

It is not a de Polignac number, because 128393449 - 2⁵ = 128393417 is a prime.

It is a super-2 number, since 2×128393449² = 32969755492231202, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128393149) 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, 430702 + ... + 430999.

It is an arithmetic number, because the mean of its divisors is an integer number (32313825).

Almost surely, 2^128393449 is an apocalyptic number.

It is an amenable number.

128393449 is a deficient number, since it is larger than the sum of its proper divisors (861851).

128393449 is an equidigital number, since it uses as much as digits as its factorization.

128393449 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 861850.

The product of its digits is 186624, while the sum is 43.

The square root of 128393449 is about 11331.0833109637. The cubic root of 128393449 is about 504.4842612393.

The spelling of 128393449 in words is "one hundred twenty-eight million, three hundred ninety-three thousand, four hundred forty-nine".