128713321 has 4 divisors (see below), whose sum is σ = 140414544. Its totient is φ = 117012100.

The previous prime is 128713303. The next prime is 128713367. The reversal of 128713321 is 123317821.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 128713321 - 2⁹ = 128712809 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 128713321.

It is not an unprimeable number, because it can be changed into a prime (128713301) 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, 5850595 + ... + 5850616.

It is an arithmetic number, because the mean of its divisors is an integer number (35103636).

Almost surely, 2^128713321 is an apocalyptic number.

128713321 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

128713321 is a deficient number, since it is larger than the sum of its proper divisors (11701223).

128713321 is a wasteful number, since it uses less digits than its factorization.

128713321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11701222.

The product of its digits is 2016, while the sum is 28.

The square root of 128713321 is about 11345.1893329287. The cubic root of 128713321 is about 504.9028614260.

The spelling of 128713321 in words is "one hundred twenty-eight million, seven hundred thirteen thousand, three hundred twenty-one".