126720017 has 2 divisors, whose sum is σ = 126720018. Its totient is φ = 126720016.

The previous prime is 126719977. The next prime is 126720031. The reversal of 126720017 is 710027621.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 124188736 + 2531281 = 11144^2 + 1591^2 .

It is an emirp because it is prime and its reverse (710027621) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 126720017 - 2¹⁶ = 126654481 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (126720067) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 63360008 + 63360009.

It is an arithmetic number, because the mean of its divisors is an integer number (63360009).

Almost surely, 2^126720017 is an apocalyptic number.

It is an amenable number.

126720017 is a deficient number, since it is larger than the sum of its proper divisors (1).

126720017 is an equidigital number, since it uses as much as digits as its factorization.

126720017 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1176, while the sum is 26.

The square root of 126720017 is about 11256.9985786621. The cubic root of 126720017 is about 502.2829167186.

Adding to 126720017 its reverse (710027621), we get a palindrome (836747638).

The spelling of 126720017 in words is "one hundred twenty-six million, seven hundred twenty thousand, seventeen".