128321739 has 72 divisors (see below), whose sum is σ = 241091760. Its totient is φ = 67604544.

The previous prime is 128321737. The next prime is 128321771. The reversal of 128321739 is 937123821.

It is not a de Polignac number, because 128321739 - 2¹ = 128321737 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128321731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 154377 + ... + 155205.

Almost surely, 2^128321739 is an apocalyptic number.

128321739 is a deficient number, since it is larger than the sum of its proper divisors (112770021).

128321739 is an equidigital number, since it uses as much as digits as its factorization.

128321739 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 871 (or 852 counting only the distinct ones).

The product of its digits is 18144, while the sum is 36.

The square root of 128321739 is about 11327.9185643259. The cubic root of 128321739 is about 504.3903226367.

The spelling of 128321739 in words is "one hundred twenty-eight million, three hundred twenty-one thousand, seven hundred thirty-nine".