127821987 has 12 divisors (see below), whose sum is σ = 194349480. Its totient is φ = 80729568.

The previous prime is 127821977. The next prime is 127821989. The reversal of 127821987 is 789128721.

It is not a de Polignac number, because 127821987 - 2⁶ = 127821923 is a prime.

It is not an unprimeable number, because it can be changed into a prime (127821989) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 373578 + ... + 373919.

It is an arithmetic number, because the mean of its divisors is an integer number (16195790).

Almost surely, 2^127821987 is an apocalyptic number.

127821987 is a deficient number, since it is larger than the sum of its proper divisors (66527493).

127821987 is a wasteful number, since it uses less digits than its factorization.

127821987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 747522 (or 747519 counting only the distinct ones).

The product of its digits is 112896, while the sum is 45.

The square root of 127821987 is about 11305.8386243569. The cubic root of 127821987 is about 503.7346841475.

The spelling of 127821987 in words is "one hundred twenty-seven million, eight hundred twenty-one thousand, nine hundred eighty-seven".