3121231331220 has 96 divisors (see below), whose sum is σ = 8940298752000. Its totient is φ = 813258835584.

The previous prime is 3121231331209. The next prime is 3121231331279. The reversal of 3121231331220 is 221331321213.

It is a congruent 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, 765291 + ... + 2613069.

It is an arithmetic number, because the mean of its divisors is an integer number (93128112000).

Almost surely, 2^{3121231331220} is an apocalyptic number.

3121231331220 is a gapful number since it is divisible by the number (30) 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 3121231331220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4470149376000).

3121231331220 is an abundant number, since it is smaller than the sum of its proper divisors (5819067420780).

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

3121231331220 is a wasteful number, since it uses less digits than its factorization.

3121231331220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1848437 (or 1848435 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 24.

Adding to 3121231331220 its reverse (221331321213), we get a palindrome (3342562652433).

The spelling of 3121231331220 in words is "three trillion, one hundred twenty-one billion, two hundred thirty-one million, three hundred thirty-one thousand, two hundred twenty".