31213021300000 has 144 divisors (see below), whose sum is σ = 76831373805480. Its totient is φ = 12481470720000.

The previous prime is 31213021299983. The next prime is 31213021300001. The reversal of 31213021300000 is 312031213.

It can be written as a sum of positive squares in 12 ways, for example, as 14297140696336 + 16915880603664 = 3781156^2 + 4112892^2 .

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

It is not an unprimeable number, because it can be changed into a prime (31213021300001) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 346855012 + ... + 346944988.

Almost surely, 2^{31213021300000} 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 31213021300000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38415686902740).

31213021300000 is an abundant number, since it is smaller than the sum of its proper divisors (45618352505480).

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

31213021300000 is an frugal number, since it uses more digits than its factorization.

31213021300000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93481 (or 93453 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 16.

Adding to 31213021300000 its reverse (312031213), we get a palindrome (31213333331213).

The spelling of 31213021300000 in words is "thirty-one trillion, two hundred thirteen billion, twenty-one million, three hundred thousand".