128785331 has 2 divisors, whose sum is σ = 128785332. Its totient is φ = 128785330.

The previous prime is 128785291. The next prime is 128785351. The reversal of 128785331 is 133587821.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 128785331 - 2²⁶ = 61676467 is a prime.

It is a super-2 number, since 2×128785331² = 33171322961559122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (128785351) 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 as a sum of consecutive naturals, namely, 64392665 + 64392666.

It is an arithmetic number, because the mean of its divisors is an integer number (64392666).

Almost surely, 2^128785331 is an apocalyptic number.

128785331 is a deficient number, since it is larger than the sum of its proper divisors (1).

128785331 is an equidigital number, since it uses as much as digits as its factorization.

128785331 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 40320, while the sum is 38.

The square root of 128785331 is about 11348.3624809926. The cubic root of 128785331 is about 504.9970015833.

The spelling of 128785331 in words is "one hundred twenty-eight million, seven hundred eighty-five thousand, three hundred thirty-one".