128836231 has 4 divisors (see below), whose sum is σ = 128884392. Its totient is φ = 128788072.

The previous prime is 128836229. The next prime is 128836261. The reversal of 128836231 is 132638821.

It is a happy number.

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 128836231 - 2¹ = 128836229 is a prime.

It is a super-2 number, since 2×128836231² = 33197548836570722, 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 (128836261) 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, 19816 + ... + 25501.

It is an arithmetic number, because the mean of its divisors is an integer number (32221098).

Almost surely, 2^128836231 is an apocalyptic number.

128836231 is a deficient number, since it is larger than the sum of its proper divisors (48161).

128836231 is an equidigital number, since it uses as much as digits as its factorization.

128836231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48160.

The product of its digits is 13824, while the sum is 34.

The square root of 128836231 is about 11350.6048737501. The cubic root of 128836231 is about 505.0635230356.

The spelling of 128836231 in words is "one hundred twenty-eight million, eight hundred thirty-six thousand, two hundred thirty-one".