127873677821 has 2 divisors, whose sum is σ = 127873677822. Its totient is φ = 127873677820.

The previous prime is 127873677791. The next prime is 127873677917. The reversal of 127873677821 is 128776378721.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 117690849721 + 10182828100 = 343061^2 + 100910^2 .

It is a cyclic number.

It is not a de Polignac number, because 127873677821 - 2¹⁰ = 127873676797 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (127873677721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 63936838910 + 63936838911.

It is an arithmetic number, because the mean of its divisors is an integer number (63936838911).

Almost surely, 2^127873677821 is an apocalyptic number.

It is an amenable number.

127873677821 is a deficient number, since it is larger than the sum of its proper divisors (1).

127873677821 is an equidigital number, since it uses as much as digits as its factorization.

127873677821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11063808, while the sum is 59.

The spelling of 127873677821 in words is "one hundred twenty-seven billion, eight hundred seventy-three million, six hundred seventy-seven thousand, eight hundred twenty-one".