31312221213312 has 192 divisors, whose sum is σ = 97421875256160. Its totient is φ = 9596143872000.

The previous prime is 31312221213269. The next prime is 31312221213353. The reversal of 31312221213312 is 21331212221313.

31312221213312 is a `hidden beast` number, since 3 + 1 + 3 + 1 + 222 + 121 + 3 + 312 = 666.

It is a tau number, because it is divible by the number of its divisors (192).

It is a super-2 number, since 2×31312221213312² (a number of 28 digits) contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 406018 + ... + 7923969.

Almost surely, 2^{31312221213312} is an apocalyptic number.

31312221213312 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 31312221213312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48710937628080).

31312221213312 is an abundant number, since it is smaller than the sum of its proper divisors (66109654042848).

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

31312221213312 is a wasteful number, since it uses less digits than its factorization.

31312221213312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8330271 (or 8330256 counting only the distinct ones).

The product of its digits is 2592, while the sum is 27.

Adding to 31312221213312 its reverse (21331212221313), we get a palindrome (52643433434625).

The spelling of 31312221213312 in words is "thirty-one trillion, three hundred twelve billion, two hundred twenty-one million, two hundred thirteen thousand, three hundred twelve".