85915831 has 2 divisors, whose sum is σ = 85915832. Its totient is φ = 85915830.

The previous prime is 85915799. The next prime is 85915861. The reversal of 85915831 is 13851958.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 85915831 - 2⁵ = 85915799 is a prime.

It is a super-2 number, since 2×85915831² = 14763060032841122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (85915861) 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, 42957915 + 42957916.

It is an arithmetic number, because the mean of its divisors is an integer number (42957916).

Almost surely, 2^85915831 is an apocalyptic number.

85915831 is a deficient number, since it is larger than the sum of its proper divisors (1).

85915831 is an equidigital number, since it uses as much as digits as its factorization.

85915831 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 43200, while the sum is 40.

The square root of 85915831 is about 9269.0792962408. The cubic root of 85915831 is about 441.2564483164.

The spelling of 85915831 in words is "eighty-five million, nine hundred fifteen thousand, eight hundred thirty-one".