231111312221020 has 192 divisors, whose sum is σ = 605770041139200. Its totient is φ = 71953954617600.

The previous prime is 231111312220871. The next prime is 231111312221039. The reversal of 231111312221020 is 20122213111132.

It is a happy number.

231111312221020 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a junction number, because it is equal to n+sod(n) for n = 231111312220982 and 231111312221000.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 5194540975 + ... + 5194585465.

It is an arithmetic number, because the mean of its divisors is an integer number (3155052297600).

Almost surely, 2^{231111312221020} is an apocalyptic number.

231111312221020 is a gapful number since it is divisible by the number (20) 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 231111312221020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (302885020569600).

231111312221020 is an abundant number, since it is smaller than the sum of its proper divisors (374658728918180).

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

231111312221020 is a wasteful number, since it uses less digits than its factorization.

231111312221020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48224 (or 48222 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 22.

Adding to 231111312221020 its reverse (20122213111132), we get a palindrome (251233525332152).

The spelling of 231111312221020 in words is "two hundred thirty-one trillion, one hundred eleven billion, three hundred twelve million, two hundred twenty-one thousand, twenty".