220831 has 4 divisors (see below), whose sum is σ = 237832. Its totient is φ = 203832.

The previous prime is 220811. The next prime is 220841. The reversal of 220831 is 138022.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 138022 = 2 ⋅69011.

It is a cyclic number.

It is not a de Polignac number, because 220831 - 2¹¹ = 218783 is a prime.

It is a super-2 number, since 2×220831² = 97532661122, which contains 22 as substring.

It is a Duffinian number.

It is a nialpdrome in base 6.

It is a zygodrome in base 6.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (220811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8481 + ... + 8506.

It is an arithmetic number, because the mean of its divisors is an integer number (59458).

2²²⁰⁸³¹ is an apocalyptic number.

220831 is a deficient number, since it is larger than the sum of its proper divisors (17001).

220831 is a wasteful number, since it uses less digits than its factorization.

220831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17000.

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 220831 is about 469.9265900117. The cubic root of 220831 is about 60.4440208013. Note that the first 3 decimals are identical.

Adding to 220831 its reverse (138022), we get a palindrome (358853).

The spelling of 220831 in words is "two hundred twenty thousand, eight hundred thirty-one".