127999999 has 4 divisors (see below), whose sum is σ = 128024064. Its totient is φ = 127975936.

The previous prime is 127999981. The next prime is 128000003. The reversal of 127999999 is 999999721.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 127999999 - 2⁵ = 127999967 is a prime.

It is a Duffinian number.

127999999 is a modest number, since divided by 99999 gives 1279 as remainder.

It is a plaindrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 127999999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (127999099) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 127 + ... + 16000.

It is an arithmetic number, because the mean of its divisors is an integer number (32006016).

Almost surely, 2^127999999 is an apocalyptic number.

127999999 is a deficient number, since it is larger than the sum of its proper divisors (24065).

127999999 is an equidigital number, since it uses as much as digits as its factorization.

127999999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24064.

The product of its digits is 7440174, while the sum is 64.

The square root of 127999999 is about 11313.7084547906. The cubic root of 127999999 is about 503.9684186455.

It can be divided in two parts, 1279 and 99999, that multiplied together give a palindrome (127898721).

The spelling of 127999999 in words is "one hundred twenty-seven million, nine hundred ninety-nine thousand, nine hundred ninety-nine".