128209279 has 16 divisors (see below), whose sum is σ = 145566720. Its totient is φ = 111897760.

The previous prime is 128209267. The next prime is 128209309. The reversal of 128209279 is 972902821.

It is a cyclic number.

It is not a de Polignac number, because 128209279 - 2⁹ = 128208767 is a prime.

It is a super-3 number, since 3×128209279³ (a number of 25 digits) contains 333 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 (128209079) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25062 + ... + 29740.

It is an arithmetic number, because the mean of its divisors is an integer number (9097920).

Almost surely, 2^128209279 is an apocalyptic number.

128209279 is a deficient number, since it is larger than the sum of its proper divisors (17357441).

128209279 is a wasteful number, since it uses less digits than its factorization.

128209279 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4790.

The product of its (nonzero) digits is 36288, while the sum is 40.

The square root of 128209279 is about 11322.9536341010. The cubic root of 128209279 is about 504.2429318804.

The spelling of 128209279 in words is "one hundred twenty-eight million, two hundred nine thousand, two hundred seventy-nine".