127891 has 4 divisors (see below), whose sum is σ = 135432. Its totient is φ = 120352.

The previous prime is 127877. The next prime is 127913. The reversal of 127891 is 198721.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 198721 = 19 ⋅10459.

It is a cyclic number.

It is not a de Polignac number, because 127891 - 2⁵ = 127859 is a prime.

It is a super-2 number, since 2×127891² = 32712215762, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (127291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3745 + ... + 3778.

It is an arithmetic number, because the mean of its divisors is an integer number (33858).

2¹²⁷⁸⁹¹ is an apocalyptic number.

127891 is a deficient number, since it is larger than the sum of its proper divisors (7541).

127891 is an equidigital number, since it uses as much as digits as its factorization.

127891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7540.

The product of its digits is 1008, while the sum is 28.

The square root of 127891 is about 357.6185118251. The cubic root of 127891 is about 50.3825325797.

It can be divided in two parts, 1278 and 91, that added together give a square (1369 = 37²).

The spelling of 127891 in words is "one hundred twenty-seven thousand, eight hundred ninety-one".