126565409 has 2 divisors, whose sum is σ = 126565410. Its totient is φ = 126565408.

The previous prime is 126565379. The next prime is 126565427. The reversal of 126565409 is 904565621.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 120670225 + 5895184 = 10985^2 + 2428^2 .

It is an emirp because it is prime and its reverse (904565621) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-126565409 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (126565489) 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, 63282704 + 63282705.

It is an arithmetic number, because the mean of its divisors is an integer number (63282705).

Almost surely, 2^126565409 is an apocalyptic number.

It is an amenable number.

126565409 is a deficient number, since it is larger than the sum of its proper divisors (1).

126565409 is an equidigital number, since it uses as much as digits as its factorization.

126565409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 64800, while the sum is 38.

The square root of 126565409 is about 11250.1292881460. The cubic root of 126565409 is about 502.0785592096.

The spelling of 126565409 in words is "one hundred twenty-six million, five hundred sixty-five thousand, four hundred nine".