31869 has 6 divisors (see below), whose sum is σ = 46046. Its totient is φ = 21240.

The previous prime is 31859. The next prime is 31873. The reversal of 31869 is 96813.

It can be written as a sum of positive squares in only one way, i.e., 26244 + 5625 = 162^2 + 75^2 .

It is not a de Polignac number, because 31869 - 2⁷ = 31741 is a prime.

It is a super-2 number, since 2×31869² = 2031266322, which contains 22 as substring.

It is a Duffinian number.

31869 is a lucky number.

It is a nialpdrome in base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31849) 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 5 ways as a sum of consecutive naturals, for example, 1762 + ... + 1779.

2³¹⁸⁶⁹ is an apocalyptic number.

It is an amenable number.

31869 is a deficient number, since it is larger than the sum of its proper divisors (14177).

31869 is a wasteful number, since it uses less digits than its factorization.

31869 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3547 (or 3544 counting only the distinct ones).

The product of its digits is 1296, while the sum is 27.

The square root of 31869 is about 178.5189065617. The cubic root of 31869 is about 31.7046389666.

It can be divided in two parts, 31 and 869, that added together give a square (900 = 30²).

The spelling of 31869 in words is "thirty-one thousand, eight hundred sixty-nine".