12520172121 has 8 divisors (see below), whose sum is σ = 17675537184. Its totient is φ = 7855794240.

The previous prime is 12520172057. The next prime is 12520172141. The reversal of 12520172121 is 12127102521.

It is a happy number.

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

It is not a de Polignac number, because 12520172121 - 2⁶ = 12520172057 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 12520172091 and 12520172100.

It is not an unprimeable number, because it can be changed into a prime (12520172141) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 122746735 + ... + 122746836.

It is an arithmetic number, because the mean of its divisors is an integer number (2209442148).

Almost surely, 2^12520172121 is an apocalyptic number.

It is an amenable number.

12520172121 is a deficient number, since it is larger than the sum of its proper divisors (5155365063).

12520172121 is a wasteful number, since it uses less digits than its factorization.

12520172121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 245493591.

The product of its (nonzero) digits is 560, while the sum is 24.

Adding to 12520172121 its reverse (12127102521), we get a palindrome (24647274642).

The spelling of 12520172121 in words is "twelve billion, five hundred twenty million, one hundred seventy-two thousand, one hundred twenty-one".