31212231223 has 4 divisors (see below), whose sum is σ = 31217173848. Its totient is φ = 31207288600.

The previous prime is 31212231187. The next prime is 31212231227. The reversal of 31212231223 is 32213221213.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32213221213 = 73237 ⋅439849.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31212231223 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31212231194 and 31212231203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31212231227) 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, 2461828 + ... + 2474473.

It is an arithmetic number, because the mean of its divisors is an integer number (7804293462).

Almost surely, 2^31212231223 is an apocalyptic number.

31212231223 is a deficient number, since it is larger than the sum of its proper divisors (4942625).

31212231223 is an equidigital number, since it uses as much as digits as its factorization.

31212231223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4942624.

The product of its digits is 864, while the sum is 22.

Adding to 31212231223 its reverse (32213221213), we get a palindrome (63425452436).

The spelling of 31212231223 in words is "thirty-one billion, two hundred twelve million, two hundred thirty-one thousand, two hundred twenty-three".