128421347 has 4 divisors (see below), whose sum is σ = 130598040. Its totient is φ = 126244656.

The previous prime is 128421341. The next prime is 128421353. The reversal of 128421347 is 743124821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 743124821 = 11923 ⋅62327.

It is an interprime number because it is at equal distance from previous prime (128421341) and next prime (128421353).

It is a cyclic number.

It is not a de Polignac number, because 128421347 - 2⁴ = 128421331 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128421341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1088258 + ... + 1088375.

It is an arithmetic number, because the mean of its divisors is an integer number (32649510).

Almost surely, 2^128421347 is an apocalyptic number.

128421347 is a deficient number, since it is larger than the sum of its proper divisors (2176693).

128421347 is an equidigital number, since it uses as much as digits as its factorization.

128421347 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2176692.

The product of its digits is 10752, while the sum is 32.

The square root of 128421347 is about 11332.3142826168. The cubic root of 128421347 is about 504.5207975860.

The spelling of 128421347 in words is "one hundred twenty-eight million, four hundred twenty-one thousand, three hundred forty-seven".