12771770891 has 4 divisors (see below), whose sum is σ = 13932840984. Its totient is φ = 11610700800.

The previous prime is 12771770813. The next prime is 12771770909. The reversal of 12771770891 is 19807717721.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12771770891 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12771760891) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 580535030 + ... + 580535051.

It is an arithmetic number, because the mean of its divisors is an integer number (3483210246).

Almost surely, 2^12771770891 is an apocalyptic number.

12771770891 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

12771770891 is a deficient number, since it is larger than the sum of its proper divisors (1161070093).

12771770891 is a wasteful number, since it uses less digits than its factorization.

12771770891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1161070092.

The product of its (nonzero) digits is 345744, while the sum is 50.

The spelling of 12771770891 in words is "twelve billion, seven hundred seventy-one million, seven hundred seventy thousand, eight hundred ninety-one".