31123112020 has 192 divisors, whose sum is σ = 89067718656. Its totient is φ = 8820472320.

The previous prime is 31123112017. The next prime is 31123112021. The reversal of 31123112020 is 2021132113.

It is a junction number, because it is equal to n+sod(n) for n = 31123111985 and 31123112003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31123112021) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1329739 + ... + 1352941.

It is an arithmetic number, because the mean of its divisors is an integer number (463894368).

Almost surely, 2^31123112020 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 31123112020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44533859328).

31123112020 is an abundant number, since it is smaller than the sum of its proper divisors (57944606636).

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

31123112020 is a wasteful number, since it uses less digits than its factorization.

31123112020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23310 (or 23308 counting only the distinct ones).

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

Adding to 31123112020 its reverse (2021132113), we get a palindrome (33144244133).

The spelling of 31123112020 in words is "thirty-one billion, one hundred twenty-three million, one hundred twelve thousand, twenty".