12553515421 has 2 divisors, whose sum is σ = 12553515422. Its totient is φ = 12553515420.

The previous prime is 12553515383. The next prime is 12553515427. The reversal of 12553515421 is 12451535521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8758339396 + 3795176025 = 93586^2 + 61605^2 .

It is an emirp because it is prime and its reverse (12451535521) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12553515421 - 2¹⁹ = 12552991133 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12553515427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6276757710 + 6276757711.

It is an arithmetic number, because the mean of its divisors is an integer number (6276757711).

Almost surely, 2^12553515421 is an apocalyptic number.

It is an amenable number.

12553515421 is a deficient number, since it is larger than the sum of its proper divisors (1).

12553515421 is an equidigital number, since it uses as much as digits as its factorization.

12553515421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 30000, while the sum is 34.

The spelling of 12553515421 in words is "twelve billion, five hundred fifty-three million, five hundred fifteen thousand, four hundred twenty-one".