13111231021020 has 288 divisors, whose sum is σ = 45859275221760. Its totient is φ = 2998695168000.

The previous prime is 13111231020971. The next prime is 13111231021043. The reversal of 13111231021020 is 2012013211131.

13111231021020 is a `hidden beast` number, since 1 + 31 + 112 + 310 + 210 + 2 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 13111231020984 and 13111231021002.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 8343355 + ... + 9789485.

It is an arithmetic number, because the mean of its divisors is an integer number (159233594520).

Almost surely, 2^{13111231021020} is an apocalyptic number.

13111231021020 is a gapful number since it is divisible by the number (10) 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 13111231021020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22929637610880).

13111231021020 is an abundant number, since it is smaller than the sum of its proper divisors (32748044200740).

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

13111231021020 is a wasteful number, since it uses less digits than its factorization.

13111231021020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1446417 (or 1446412 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

Adding to 13111231021020 its reverse (2012013211131), we get a palindrome (15123244232151).

The spelling of 13111231021020 in words is "thirteen trillion, one hundred eleven billion, two hundred thirty-one million, twenty-one thousand, twenty".