127640549 has 2 divisors, whose sum is σ = 127640550. Its totient is φ = 127640548.

The previous prime is 127640533. The next prime is 127640581. The reversal of 127640549 is 945046721.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 112508449 + 15132100 = 10607^2 + 3890^2 .

It is a cyclic number.

It is not a de Polignac number, because 127640549 - 2⁴ = 127640533 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (127640509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 63820274 + 63820275.

It is an arithmetic number, because the mean of its divisors is an integer number (63820275).

Almost surely, 2^127640549 is an apocalyptic number.

It is an amenable number.

127640549 is a deficient number, since it is larger than the sum of its proper divisors (1).

127640549 is an equidigital number, since it uses as much as digits as its factorization.

127640549 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 60480, while the sum is 38.

The square root of 127640549 is about 11297.8116907656. The cubic root of 127640549 is about 503.4962278003.

The spelling of 127640549 in words is "one hundred twenty-seven million, six hundred forty thousand, five hundred forty-nine".