128330381 has 2 divisors, whose sum is σ = 128330382. Its totient is φ = 128330380.

The previous prime is 128330357. The next prime is 128330407. The reversal of 128330381 is 183033821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 81613156 + 46717225 = 9034^2 + 6835^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128330381 is a prime.

It is a super-2 number, since 2×128330381² = 32937373375210322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128330341) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64165190 + 64165191.

It is an arithmetic number, because the mean of its divisors is an integer number (64165191).

Almost surely, 2^128330381 is an apocalyptic number.

It is an amenable number.

128330381 is a deficient number, since it is larger than the sum of its proper divisors (1).

128330381 is an equidigital number, since it uses as much as digits as its factorization.

128330381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 128330381 is about 11328.3000048551. The cubic root of 128330381 is about 504.4016453306.

The spelling of 128330381 in words is "one hundred twenty-eight million, three hundred thirty thousand, three hundred eighty-one".