100031213 has 4 divisors (see below), whose sum is σ = 105915420. Its totient is φ = 94147008.

The previous prime is 100031189. The next prime is 100031263. The reversal of 100031213 is 312130001.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 312130001 = 59 ⋅5290339.

It can be written as a sum of positive squares in 2 ways, for example, as 80335369 + 19695844 = 8963^2 + 4438^2 .

It is a cyclic number.

It is not a de Polignac number, because 100031213 - 2¹² = 100027117 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 100031194 and 100031203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100031263) 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, 2942078 + ... + 2942111.

It is an arithmetic number, because the mean of its divisors is an integer number (26478855).

Almost surely, 2^100031213 is an apocalyptic number.

It is an amenable number.

100031213 is a deficient number, since it is larger than the sum of its proper divisors (5884207).

100031213 is an equidigital number, since it uses as much as digits as its factorization.

100031213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5884206.

The product of its (nonzero) digits is 18, while the sum is 11.

The square root of 100031213 is about 10001.5605282376. The cubic root of 100031213 is about 464.2071709750.

Adding to 100031213 its reverse (312130001), we get a palindrome (412161214).

The spelling of 100031213 in words is "one hundred million, thirty-one thousand, two hundred thirteen".