85431 has 4 divisors (see below), whose sum is σ = 113912. Its totient is φ = 56952.

The previous prime is 85429. The next prime is 85439. The reversal of 85431 is 13458.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 85431 - 2¹ = 85429 is a prime.

It is a super-2 number, since 2×85431² = 14596911522, which contains 22 as substring.

It is a D-number.

It is a Duffinian number.

It is a plaindrome in base 8.

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 85398 and 85407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (85439) 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 in 3 ways as a sum of consecutive naturals, for example, 14236 + ... + 14241.

It is an arithmetic number, because the mean of its divisors is an integer number (28478).

2⁸⁵⁴³¹ is an apocalyptic number.

85431 is a deficient number, since it is larger than the sum of its proper divisors (28481).

85431 is a wasteful number, since it uses less digits than its factorization.

85431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28480.

The product of its digits is 480, while the sum is 21.

The square root of 85431 is about 292.2858190197. The cubic root of 85431 is about 44.0424865099.

Adding to 85431 its reverse (13458), we get a palindrome (98889).

The spelling of 85431 in words is "eighty-five thousand, four hundred thirty-one".