85405831 has 16 divisors (see below), whose sum is σ = 102288384. Its totient is φ = 69721344.

The previous prime is 85405813. The next prime is 85405847. The reversal of 85405831 is 13850458.

It is not a de Polignac number, because 85405831 - 2¹³ = 85397639 is a prime.

It is a super-2 number, since 2×85405831² = 14588311937601122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (85405811) 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, 41335 + ... + 43351.

It is an arithmetic number, because the mean of its divisors is an integer number (6393024).

Almost surely, 2^85405831 is an apocalyptic number.

85405831 is a deficient number, since it is larger than the sum of its proper divisors (16882553).

85405831 is a wasteful number, since it uses less digits than its factorization.

85405831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2310.

The product of its (nonzero) digits is 19200, while the sum is 34.

The square root of 85405831 is about 9241.5275252525. The cubic root of 85405831 is about 440.3816093638.

The spelling of 85405831 in words is "eighty-five million, four hundred five thousand, eight hundred thirty-one".