31231121224231 has 2 divisors, whose sum is σ = 31231121224232. Its totient is φ = 31231121224230.

The previous prime is 31231121224223. The next prime is 31231121224243. The reversal of 31231121224231 is 13242212113213.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31231121224231 - 2³ = 31231121224223 is a prime.

It is a super-2 number, since 2×31231121224231² (a number of 28 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 31231121224231.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31231121224211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15615560612115 + 15615560612116.

It is an arithmetic number, because the mean of its divisors is an integer number (15615560612116).

Almost surely, 2^{31231121224231} is an apocalyptic number.

31231121224231 is a deficient number, since it is larger than the sum of its proper divisors (1).

31231121224231 is an equidigital number, since it uses as much as digits as its factorization.

31231121224231 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3456, while the sum is 28.

Adding to 31231121224231 its reverse (13242212113213), we get a palindrome (44473333337444).

The spelling of 31231121224231 in words is "thirty-one trillion, two hundred thirty-one billion, one hundred twenty-one million, two hundred twenty-four thousand, two hundred thirty-one".