31000120021312 has 84 divisors (see below), whose sum is σ = 66790444577340. Its totient is φ = 14269387272192.

The previous prime is 31000120021289. The next prime is 31000120021327. The reversal of 31000120021312 is 21312002100013.

It can be written as a sum of positive squares in 6 ways, for example, as 15132936256 + 30984987085056 = 123016^2 + 5566416^2 .

It is a super-2 number, since 2×31000120021312² (a number of 28 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 192364 + ... + 7876372.

Almost surely, 2^{31000120021312} is an apocalyptic number.

31000120021312 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 31000120021312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33395222288670).

31000120021312 is an abundant number, since it is smaller than the sum of its proper divisors (35790324556028).

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

31000120021312 is a wasteful number, since it uses less digits than its factorization.

31000120021312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7684420 (or 7684397 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 31000120021312 its reverse (21312002100013), we get a palindrome (52312122121325).

The spelling of 31000120021312 in words is "thirty-one trillion, one hundred twenty million, twenty-one thousand, three hundred twelve".