13121020321020 has 36 divisors (see below), whose sum is σ = 39800428307640. Its totient is φ = 3498938752224.

The previous prime is 13121020320997. The next prime is 13121020321021. The reversal of 13121020321020 is 2012302012131.

13121020321020 is a `hidden beast` number, since 1 + 312 + 10 + 2 + 0 + 321 + 0 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×13121020321020² (a number of 27 digits) contains 22 as substring.

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 = 13121020320984 and 13121020321002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13121020321021) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 36447278490 + ... + 36447278849.

It is an arithmetic number, because the mean of its divisors is an integer number (1105567452990).

Almost surely, 2^{13121020321020} is an apocalyptic number.

13121020321020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

13121020321020 is an abundant number, since it is smaller than the sum of its proper divisors (26679407986620).

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

13121020321020 is a wasteful number, since it uses less digits than its factorization.

13121020321020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72894557354 (or 72894557349 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 13121020321020 its reverse (2012302012131), we get a palindrome (15133322333151).

The spelling of 13121020321020 in words is "thirteen trillion, one hundred twenty-one billion, twenty million, three hundred twenty-one thousand, twenty".