31211321123 has 4 divisors (see below), whose sum is σ = 31221461040. Its totient is φ = 31201181208.

The previous prime is 31211321117. The next prime is 31211321159. The reversal of 31211321123 is 32112311213.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 31211321123 - 2⁶ = 31211321059 is a prime.

It is a super-2 number, since 2×31211321123² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31211321095 and 31211321104.

It is not an unprimeable number, because it can be changed into a prime (31211321423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5065340 + ... + 5071497.

It is an arithmetic number, because the mean of its divisors is an integer number (7805365260).

Almost surely, 2^31211321123 is an apocalyptic number.

31211321123 is a deficient number, since it is larger than the sum of its proper divisors (10139917).

31211321123 is a wasteful number, since it uses less digits than its factorization.

31211321123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10139916.

The product of its digits is 216, while the sum is 20.

Adding to 31211321123 its reverse (32112311213), we get a palindrome (63323632336).

The spelling of 31211321123 in words is "thirty-one billion, two hundred eleven million, three hundred twenty-one thousand, one hundred twenty-three".