128673431 has 6 divisors (see below), whose sum is σ = 134511720. Its totient is φ = 123078428.

The previous prime is 128673427. The next prime is 128673449. The reversal of 128673431 is 134376821.

It is not a de Polignac number, because 128673431 - 2² = 128673427 is a prime.

It is a super-2 number, since 2×128673431² = 33113703690623522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 128673391 and 128673400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128673331) 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 5 ways as a sum of consecutive naturals, for example, 121091 + ... + 122148.

It is an arithmetic number, because the mean of its divisors is an integer number (22418620).

Almost surely, 2^128673431 is an apocalyptic number.

128673431 is a deficient number, since it is larger than the sum of its proper divisors (5838289).

128673431 is an equidigital number, since it uses as much as digits as its factorization.

128673431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 243285 (or 243262 counting only the distinct ones).

The product of its digits is 24192, while the sum is 35.

The square root of 128673431 is about 11343.4311828476. The cubic root of 128673431 is about 504.8506972937.

It can be divided in two parts, 128 and 673431, that multiplied together give a palindrome (86199168).

The spelling of 128673431 in words is "one hundred twenty-eight million, six hundred seventy-three thousand, four hundred thirty-one".