12509734921 has 2 divisors, whose sum is σ = 12509734922. Its totient is φ = 12509734920.

The previous prime is 12509734859. The next prime is 12509734933. The reversal of 12509734921 is 12943790521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11682367225 + 827367696 = 108085^2 + 28764^2 .

It is an emirp because it is prime and its reverse (12943790521) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12509734921 - 2²⁹ = 11972864009 is a prime.

It is not a weakly prime, because it can be changed into another prime (12509734981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6254867460 + 6254867461.

It is an arithmetic number, because the mean of its divisors is an integer number (6254867461).

Almost surely, 2^12509734921 is an apocalyptic number.

It is an amenable number.

12509734921 is a deficient number, since it is larger than the sum of its proper divisors (1).

12509734921 is an equidigital number, since it uses as much as digits as its factorization.

12509734921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 136080, while the sum is 43.

The spelling of 12509734921 in words is "twelve billion, five hundred nine million, seven hundred thirty-four thousand, nine hundred twenty-one".