127664491 has 2 divisors, whose sum is σ = 127664492. Its totient is φ = 127664490.

The previous prime is 127664437. The next prime is 127664507. The reversal of 127664491 is 194466721.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 127664491 - 2¹³ = 127656299 is a prime.

It is not a weakly prime, because it can be changed into another prime (127664791) 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, 63832245 + 63832246.

It is an arithmetic number, because the mean of its divisors is an integer number (63832246).

Almost surely, 2^127664491 is an apocalyptic number.

127664491 is a deficient number, since it is larger than the sum of its proper divisors (1).

127664491 is an equidigital number, since it uses as much as digits as its factorization.

127664491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 72576, while the sum is 40.

The square root of 127664491 is about 11298.8712268085. The cubic root of 127664491 is about 503.5277067024.

The spelling of 127664491 in words is "one hundred twenty-seven million, six hundred sixty-four thousand, four hundred ninety-one".