127697561 has 2 divisors, whose sum is σ = 127697562. Its totient is φ = 127697560.

The previous prime is 127697539. The next prime is 127697569. The reversal of 127697561 is 165796721.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 70241161 + 57456400 = 8381^2 + 7580^2 .

It is an emirp because it is prime and its reverse (165796721) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 127697561 - 2⁶ = 127697497 is a prime.

It is not a weakly prime, because it can be changed into another prime (127697569) 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, 63848780 + 63848781.

It is an arithmetic number, because the mean of its divisors is an integer number (63848781).

Almost surely, 2^127697561 is an apocalyptic number.

It is an amenable number.

127697561 is a deficient number, since it is larger than the sum of its proper divisors (1).

127697561 is an equidigital number, since it uses as much as digits as its factorization.

127697561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 158760, while the sum is 44.

The square root of 127697561 is about 11300.3345525697. The cubic root of 127697561 is about 503.5711806121.

The spelling of 127697561 in words is "one hundred twenty-seven million, six hundred ninety-seven thousand, five hundred sixty-one".