12566551 has 2 divisors, whose sum is σ = 12566552. Its totient is φ = 12566550.

The previous prime is 12566539. The next prime is 12566557. The reversal of 12566551 is 15566521.

It is a strong prime.

It is an emirp because it is prime and its reverse (15566521) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12566551 - 2¹⁹ = 12042263 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12566557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6283275 + 6283276.

It is an arithmetic number, because the mean of its divisors is an integer number (6283276).

Almost surely, 2^12566551 is an apocalyptic number.

12566551 is a deficient number, since it is larger than the sum of its proper divisors (1).

12566551 is an equidigital number, since it uses as much as digits as its factorization.

12566551 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9000, while the sum is 31.

The square root of 12566551 is about 3544.9331446446. The cubic root of 12566551 is about 232.4905827303.

The spelling of 12566551 in words is "twelve million, five hundred sixty-six thousand, five hundred fifty-one".