1231112020021 has 24 divisors (see below), whose sum is σ = 1346627136456. Its totient is φ = 1124883302400.

The previous prime is 1231112020013. The next prime is 1231112020027. The reversal of 1231112020021 is 1200202111321.

It can be written as a sum of positive squares in 12 ways, for example, as 424778062500 + 806333957521 = 651750^2 + 897961^2 .

It is not a de Polignac number, because 1231112020021 - 2³ = 1231112020013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1231112019977 and 1231112020004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1231112020027) 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, 108433681 + ... + 108445033.

It is an arithmetic number, because the mean of its divisors is an integer number (56109464019).

Almost surely, 2^{1231112020021} is an apocalyptic number.

It is an amenable number.

1231112020021 is a deficient number, since it is larger than the sum of its proper divisors (115515116435).

1231112020021 is a wasteful number, since it uses less digits than its factorization.

1231112020021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17833 (or 17820 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 1231112020021 its reverse (1200202111321), we get a palindrome (2431314131342).

The spelling of 1231112020021 in words is "one trillion, two hundred thirty-one billion, one hundred twelve million, twenty thousand, twenty-one".