208831 has 4 divisors (see below), whose sum is σ = 238672. Its totient is φ = 178992.

The previous prime is 208807. The next prime is 208837. The reversal of 208831 is 138802.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 138802 = 2 ⋅69401.

It is a cyclic number.

It is not a de Polignac number, because 208831 - 2⁵ = 208799 is a prime.

It is a super-2 number, since 2×208831² = 87220773122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (208837) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14910 + ... + 14923.

It is an arithmetic number, because the mean of its divisors is an integer number (59668).

2²⁰⁸⁸³¹ is an apocalyptic number.

208831 is a deficient number, since it is larger than the sum of its proper divisors (29841).

208831 is an equidigital number, since it uses as much as digits as its factorization.

208831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29840.

The product of its (nonzero) digits is 384, while the sum is 22.

The square root of 208831 is about 456.9803059214. The cubic root of 208831 is about 59.3287214640.

The spelling of 208831 in words is "two hundred eight thousand, eight hundred thirty-one".