15221232121 has 8 divisors (see below), whose sum is σ = 15437991744. Its totient is φ = 15004538640.

The previous prime is 15221232119. The next prime is 15221232133. The reversal of 15221232121 is 12123212251.

15221232121 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 15221232121 - 2¹ = 15221232119 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 15221232092 and 15221232101.

It is not an unprimeable number, because it can be changed into a prime (15221232181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 619350 + ... + 643456.

It is an arithmetic number, because the mean of its divisors is an integer number (1929748968).

Almost surely, 2^15221232121 is an apocalyptic number.

It is an amenable number.

15221232121 is a deficient number, since it is larger than the sum of its proper divisors (216759623).

15221232121 is an equidigital number, since it uses as much as digits as its factorization.

15221232121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33071.

The product of its digits is 480, while the sum is 22.

Adding to 15221232121 its reverse (12123212251), we get a palindrome (27344444372).

The spelling of 15221232121 in words is "fifteen billion, two hundred twenty-one million, two hundred thirty-two thousand, one hundred twenty-one".