85128135091 has 2 divisors, whose sum is σ = 85128135092. Its totient is φ = 85128135090.

The previous prime is 85128135013. The next prime is 85128135107. The reversal of 85128135091 is 19053182158.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 85128135091 - 2⁹ = 85128134579 is a prime.

It is not a weakly prime, because it can be changed into another prime (85128135791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42564067545 + 42564067546.

It is an arithmetic number, because the mean of its divisors is an integer number (42564067546).

Almost surely, 2^85128135091 is an apocalyptic number.

85128135091 is a deficient number, since it is larger than the sum of its proper divisors (1).

85128135091 is an equidigital number, since it uses as much as digits as its factorization.

85128135091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 86400, while the sum is 43.

The spelling of 85128135091 in words is "eighty-five billion, one hundred twenty-eight million, one hundred thirty-five thousand, ninety-one".