127783991 has 6 divisors (see below), whose sum is σ = 128395176. Its totient is φ = 127174400.

The previous prime is 127783973. The next prime is 127783993. The reversal of 127783991 is 199387721.

It is not a de Polignac number, because 127783991 - 2⁶ = 127783927 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (127783993) by changing a digit.

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 in 5 ways as a sum of consecutive naturals, for example, 199031 + ... + 199671.

It is an arithmetic number, because the mean of its divisors is an integer number (21399196).

Almost surely, 2^127783991 is an apocalyptic number.

127783991 is a deficient number, since it is larger than the sum of its proper divisors (611185).

127783991 is an frugal number, since it uses more digits than its factorization.

127783991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1593 (or 952 counting only the distinct ones).

The product of its digits is 190512, while the sum is 47.

The square root of 127783991 is about 11304.1581287595. The cubic root of 127783991 is about 503.6847662882.

The spelling of 127783991 in words is "one hundred twenty-seven million, seven hundred eighty-three thousand, nine hundred ninety-one".