100031 has 4 divisors (see below), whose sum is σ = 101592. Its totient is φ = 98472.

The previous prime is 100019. The next prime is 100043. The reversal of 100031 is 130001.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 130001 = 71 ⋅1831.

It is an interprime number because it is at equal distance from previous prime (100019) and next prime (100043).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-100031 is a prime.

It is a super-2 number, since 2×100031² = 20012401922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 99988 and 100024.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100931) 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 3 ways as a sum of consecutive naturals, for example, 680 + ... + 813.

It is an arithmetic number, because the mean of its divisors is an integer number (25398).

2¹⁰⁰⁰³¹ is an apocalyptic number.

100031 is a deficient number, since it is larger than the sum of its proper divisors (1561).

100031 is an equidigital number, since it uses as much as digits as its factorization.

100031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1560.

The product of its (nonzero) digits is 3, while the sum is 5.

The square root of 100031 is about 316.2767775225. The cubic root of 100031 is about 46.4206841491.

Adding to 100031 its reverse (130001), we get a palindrome (230032).

The spelling of 100031 in words is "one hundred thousand, thirty-one".