127989621028 has 6 divisors (see below), whose sum is σ = 223981836806. Its totient is φ = 63994810512.

The previous prime is 127989620999. The next prime is 127989621073. The reversal of 127989621028 is 820126989721.

It can be written as a sum of positive squares in only one way, i.e., 84909297664 + 43080323364 = 291392^2 + 207558^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 127989621028.

It is an unprimeable number.

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, 15998702625 + ... + 15998702632.

Almost surely, 2^127989621028 is an apocalyptic number.

It is an amenable number.

127989621028 is a deficient number, since it is larger than the sum of its proper divisors (95992215778).

127989621028 is a wasteful number, since it uses less digits than its factorization.

127989621028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31997405261 (or 31997405259 counting only the distinct ones).

The product of its (nonzero) digits is 1741824, while the sum is 55.

The spelling of 127989621028 in words is "one hundred twenty-seven billion, nine hundred eighty-nine million, six hundred twenty-one thousand, twenty-eight".