127771544021 has 4 divisors (see below), whose sum is σ = 139387138944. Its totient is φ = 116155949100.

The previous prime is 127771543829. The next prime is 127771544053. The reversal of 127771544021 is 120445177721.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 127771544021 - 2¹⁸ = 127771281877 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 127771544021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (127771544521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5807797445 + ... + 5807797466.

It is an arithmetic number, because the mean of its divisors is an integer number (34846784736).

Almost surely, 2^127771544021 is an apocalyptic number.

127771544021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

127771544021 is a deficient number, since it is larger than the sum of its proper divisors (11615594923).

127771544021 is a wasteful number, since it uses less digits than its factorization.

127771544021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11615594922.

The product of its (nonzero) digits is 109760, while the sum is 41.

The spelling of 127771544021 in words is "one hundred twenty-seven billion, seven hundred seventy-one million, five hundred forty-four thousand, twenty-one".