128820319 has 4 divisors (see below), whose sum is σ = 131962320. Its totient is φ = 125678320.

The previous prime is 128820313. The next prime is 128820371. The reversal of 128820319 is 913028821.

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

It is a cyclic number.

It is not a de Polignac number, because 128820319 - 2³ = 128820311 is a prime.

It is a super-2 number, since 2×128820319² = 33189349174523522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128820311) 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, 1570939 + ... + 1571020.

It is an arithmetic number, because the mean of its divisors is an integer number (32990580).

Almost surely, 2^128820319 is an apocalyptic number.

128820319 is a deficient number, since it is larger than the sum of its proper divisors (3142001).

128820319 is an equidigital number, since it uses as much as digits as its factorization.

128820319 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3142000.

The product of its (nonzero) digits is 6912, while the sum is 34.

The square root of 128820319 is about 11349.9039202982. The cubic root of 128820319 is about 505.0427294498.

The spelling of 128820319 in words is "one hundred twenty-eight million, eight hundred twenty thousand, three hundred nineteen".