128391619 has 2 divisors, whose sum is σ = 128391620. Its totient is φ = 128391618.

The previous prime is 128391533. The next prime is 128391649. The reversal of 128391619 is 916193821.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 128391619 - 2¹⁹ = 127867331 is a prime.

It is a super-2 number, since 2×128391619² = 32968815658882322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (128391649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64195809 + 64195810.

It is an arithmetic number, because the mean of its divisors is an integer number (64195810).

Almost surely, 2^128391619 is an apocalyptic number.

128391619 is a deficient number, since it is larger than the sum of its proper divisors (1).

128391619 is an equidigital number, since it uses as much as digits as its factorization.

128391619 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 23328, while the sum is 40.

The square root of 128391619 is about 11331.0025593502. The cubic root of 128391619 is about 504.4818644125.

The spelling of 128391619 in words is "one hundred twenty-eight million, three hundred ninety-one thousand, six hundred nineteen".