128338381 has 2 divisors, whose sum is σ = 128338382. Its totient is φ = 128338380.

The previous prime is 128338363. The next prime is 128338403. The reversal of 128338381 is 183833821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 97713225 + 30625156 = 9885^2 + 5534^2 .

It is an emirp because it is prime and its reverse (183833821) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 128338381 - 2⁵ = 128338349 is a prime.

It is a super-2 number, since 2×128338381² = 32941480075402322, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 128338381.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128338351) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64169190 + 64169191.

It is an arithmetic number, because the mean of its divisors is an integer number (64169191).

Almost surely, 2^128338381 is an apocalyptic number.

It is an amenable number.

128338381 is a deficient number, since it is larger than the sum of its proper divisors (1).

128338381 is an equidigital number, since it uses as much as digits as its factorization.

128338381 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27648, while the sum is 37.

The square root of 128338381 is about 11328.6530973457. The cubic root of 128338381 is about 504.4121264271.

The spelling of 128338381 in words is "one hundred twenty-eight million, three hundred thirty-eight thousand, three hundred eighty-one".