13121245221 has 16 divisors (see below), whose sum is σ = 20001244800. Its totient is φ = 7495242048.

The previous prime is 13121245217. The next prime is 13121245259. The reversal of 13121245221 is 12254212131.

It is a happy number.

It is not a de Polignac number, because 13121245221 - 2² = 13121245217 is a prime.

It is a super-2 number, since 2×13121245221² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 13121245191 and 13121245200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13121245021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 46306 + ... + 168483.

It is an arithmetic number, because the mean of its divisors is an integer number (1250077800).

Almost surely, 2^13121245221 is an apocalyptic number.

It is an amenable number.

13121245221 is a deficient number, since it is larger than the sum of its proper divisors (6879999579).

13121245221 is a wasteful number, since it uses less digits than its factorization.

13121245221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 217708.

The product of its digits is 960, while the sum is 24.

Adding to 13121245221 its reverse (12254212131), we get a palindrome (25375457352).

The spelling of 13121245221 in words is "thirteen billion, one hundred twenty-one million, two hundred forty-five thousand, two hundred twenty-one".