12521612549 has 2 divisors, whose sum is σ = 12521612550. Its totient is φ = 12521612548.

The previous prime is 12521612501. The next prime is 12521612563. The reversal of 12521612549 is 94521612521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7392904324 + 5128708225 = 85982^2 + 71615^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12521612549 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12521612569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6260806274 + 6260806275.

It is an arithmetic number, because the mean of its divisors is an integer number (6260806275).

Almost surely, 2^12521612549 is an apocalyptic number.

It is an amenable number.

12521612549 is a deficient number, since it is larger than the sum of its proper divisors (1).

12521612549 is an equidigital number, since it uses as much as digits as its factorization.

12521612549 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 43200, while the sum is 38.

The spelling of 12521612549 in words is "twelve billion, five hundred twenty-one million, six hundred twelve thousand, five hundred forty-nine".