85987831 has 16 divisors (see below), whose sum is σ = 91542528. Its totient is φ = 80640000.

The previous prime is 85987829. The next prime is 85987843. The reversal of 85987831 is 13878958.

It is a cyclic number.

It is not a de Polignac number, because 85987831 - 2¹ = 85987829 is a prime.

It is a super-2 number, since 2×85987831² = 14787814160169122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (85988831) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 334455 + ... + 334711.

It is an arithmetic number, because the mean of its divisors is an integer number (5721408).

Almost surely, 2^85987831 is an apocalyptic number.

85987831 is a deficient number, since it is larger than the sum of its proper divisors (5554697).

85987831 is a wasteful number, since it uses less digits than its factorization.

85987831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 582.

The product of its digits is 483840, while the sum is 49.

The square root of 85987831 is about 9272.9623637757. The cubic root of 85987831 is about 441.3796758721.

The spelling of 85987831 in words is "eighty-five million, nine hundred eighty-seven thousand, eight hundred thirty-one".