127640768621 has 2 divisors, whose sum is σ = 127640768622. Its totient is φ = 127640768620.

The previous prime is 127640768609. The next prime is 127640768641. The reversal of 127640768621 is 126867046721.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 78450408100 + 49190360521 = 280090^2 + 221789^2 .

It is a cyclic number.

It is not a de Polignac number, because 127640768621 - 2¹⁴ = 127640752237 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 127640768621.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (127640768641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 63820384310 + 63820384311.

It is an arithmetic number, because the mean of its divisors is an integer number (63820384311).

Almost surely, 2^127640768621 is an apocalyptic number.

It is an amenable number.

127640768621 is a deficient number, since it is larger than the sum of its proper divisors (1).

127640768621 is an equidigital number, since it uses as much as digits as its factorization.

127640768621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1354752, while the sum is 50.

The spelling of 127640768621 in words is "one hundred twenty-seven billion, six hundred forty million, seven hundred sixty-eight thousand, six hundred twenty-one".