31211300000 has 144 divisors (see below), whose sum is σ = 80851387680. Its totient is φ = 11826720000.

The previous prime is 31211299993. The next prime is 31211300017. The reversal of 31211300000 is 311213.

It is a congruent number.

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, 1891787 + ... + 1908213.

It is an arithmetic number, because the mean of its divisors is an integer number (561467970).

Almost surely, 2^31211300000 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 31211300000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40425693840).

31211300000 is an abundant number, since it is smaller than the sum of its proper divisors (49640087680).

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

31211300000 is an equidigital number, since it uses as much as digits as its factorization.

31211300000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16481 (or 16453 counting only the distinct ones).

The product of its (nonzero) digits is 18, while the sum is 11.

Adding to 31211300000 its reverse (311213), we get a palindrome (31211611213).

The spelling of 31211300000 in words is "thirty-one billion, two hundred eleven million, three hundred thousand".