13121102720 has 128 divisors (see below), whose sum is σ = 34448647680. Its totient is φ = 4739328000.

The previous prime is 13121102717. The next prime is 13121102737. The reversal of 13121102720 is 2720112131.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 13121102692 and 13121102701.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1056869 + ... + 1069211.

It is an arithmetic number, because the mean of its divisors is an integer number (269130060).

Almost surely, 2^13121102720 is an apocalyptic number.

13121102720 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 13121102720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17224323840).

13121102720 is an abundant number, since it is smaller than the sum of its proper divisors (21327544960).

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

13121102720 is a wasteful number, since it uses less digits than its factorization.

13121102720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12524 (or 12512 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 20.

Adding to 13121102720 its reverse (2720112131), we get a palindrome (15841214851).

The spelling of 13121102720 in words is "thirteen billion, one hundred twenty-one million, one hundred two thousand, seven hundred twenty".