127981546399 has 4 divisors (see below), whose sum is σ = 146264624464. Its totient is φ = 109698468336.

The previous prime is 127981546393. The next prime is 127981546409. The reversal of 127981546399 is 993645189721.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 993645189721 = 157 ⋅6328950253.

It is a cyclic number.

It is not a de Polignac number, because 127981546399 - 2³ = 127981546391 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 127981546399.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (127981546391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9141539022 + ... + 9141539035.

It is an arithmetic number, because the mean of its divisors is an integer number (36566156116).

Almost surely, 2^127981546399 is an apocalyptic number.

127981546399 is a deficient number, since it is larger than the sum of its proper divisors (18283078065).

127981546399 is an equidigital number, since it uses as much as digits as its factorization.

127981546399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18283078064.

The product of its digits is 29393280, while the sum is 64.

The spelling of 127981546399 in words is "one hundred twenty-seven billion, nine hundred eighty-one million, five hundred forty-six thousand, three hundred ninety-nine".