31321121312 has 192 divisors, whose sum is σ = 70128737280. Its totient is φ = 13671936000.

The previous prime is 31321121303. The next prime is 31321121323. The reversal of 31321121312 is 21312112313.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 181046858 + ... + 181047030.

It is an arithmetic number, because the mean of its divisors is an integer number (365253840).

Almost surely, 2^31321121312 is an apocalyptic number.

31321121312 is a gapful number since it is divisible by the number (32) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31321121312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35064368640).

31321121312 is an abundant number, since it is smaller than the sum of its proper divisors (38807615968).

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

31321121312 is a wasteful number, since it uses less digits than its factorization.

31321121312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 467 (or 459 counting only the distinct ones).

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

Adding to 31321121312 its reverse (21312112313), we get a palindrome (52633233625).

The spelling of 31321121312 in words is "thirty-one billion, three hundred twenty-one million, one hundred twenty-one thousand, three hundred twelve".