85431881545117 has 2 divisors, whose sum is σ = 85431881545118. Its totient is φ = 85431881545116.

The previous prime is 85431881545111. The next prime is 85431881545139. The reversal of 85431881545117 is 71154518813458.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 85424065040196 + 7816504921 = 9242514^2 + 88411^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-85431881545117 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (85431881545111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42715940772558 + 42715940772559.

It is an arithmetic number, because the mean of its divisors is an integer number (42715940772559).

Almost surely, 2^{85431881545117} is an apocalyptic number.

It is an amenable number.

85431881545117 is a deficient number, since it is larger than the sum of its proper divisors (1).

85431881545117 is an equidigital number, since it uses as much as digits as its factorization.

85431881545117 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21504000, while the sum is 61.

The spelling of 85431881545117 in words is "eighty-five trillion, four hundred thirty-one billion, eight hundred eighty-one million, five hundred forty-five thousand, one hundred seventeen".