12504518921 has 2 divisors, whose sum is σ = 12504518922. Its totient is φ = 12504518920.

The previous prime is 12504518909. The next prime is 12504518969. The reversal of 12504518921 is 12981540521.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6538501321 + 5966017600 = 80861^2 + 77240^2 .

It is an emirp because it is prime and its reverse (12981540521) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12504518921 - 2¹⁴ = 12504502537 is a prime.

It is not a weakly prime, because it can be changed into another prime (12504518821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6252259460 + 6252259461.

It is an arithmetic number, because the mean of its divisors is an integer number (6252259461).

Almost surely, 2^12504518921 is an apocalyptic number.

It is an amenable number.

12504518921 is a deficient number, since it is larger than the sum of its proper divisors (1).

12504518921 is an equidigital number, since it uses as much as digits as its factorization.

12504518921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 28800, while the sum is 38.

The spelling of 12504518921 in words is "twelve billion, five hundred four million, five hundred eighteen thousand, nine hundred twenty-one".