85545991 has 2 divisors, whose sum is σ = 85545992. Its totient is φ = 85545990.

The previous prime is 85545979. The next prime is 85545997. The reversal of 85545991 is 19954558.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 85545991 - 2²³ = 77157383 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (85545997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42772995 + 42772996.

It is an arithmetic number, because the mean of its divisors is an integer number (42772996).

Almost surely, 2^85545991 is an apocalyptic number.

85545991 is a deficient number, since it is larger than the sum of its proper divisors (1).

85545991 is an equidigital number, since it uses as much as digits as its factorization.

85545991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 324000, while the sum is 46.

The square root of 85545991 is about 9249.1075785721. The cubic root of 85545991 is about 440.6223819639.

The spelling of 85545991 in words is "eighty-five million, five hundred forty-five thousand, nine hundred ninety-one".