31323031212 has 96 divisors (see below), whose sum is σ = 80284861440. Its totient is φ = 9426170880.

The previous prime is 31323031189. The next prime is 31323031213. The reversal of 31323031212 is 21213032313.

It is a super-2 number, since 2×31323031212² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (31323031213) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13659138 + ... + 13661430.

It is an arithmetic number, because the mean of its divisors is an integer number (836300640).

Almost surely, 2^31323031212 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31323031212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40142430720).

31323031212 is an abundant number, since it is smaller than the sum of its proper divisors (48961830228).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31323031212 is a wasteful number, since it uses less digits than its factorization.

31323031212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2983 (or 2981 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 21.

Adding to 31323031212 its reverse (21213032313), we get a palindrome (52536063525).

The spelling of 31323031212 in words is "thirty-one billion, three hundred twenty-three million, thirty-one thousand, two hundred twelve".