27856183777921 has 4 divisors (see below), whose sum is σ = 29067322203072. Its totient is φ = 26645045352772.

The previous prime is 27856183777883. The next prime is 27856183777927. The reversal of 27856183777921 is 12977738165872.

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 27856183777921 - 2¹⁵ = 27856183745153 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (27856183777927) 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, 605569212541 + ... + 605569212586.

It is an arithmetic number, because the mean of its divisors is an integer number (7266830550768).

Almost surely, 2^{27856183777921} is an apocalyptic number.

It is an amenable number.

27856183777921 is a deficient number, since it is larger than the sum of its proper divisors (1211138425151).

27856183777921 is a wasteful number, since it uses less digits than its factorization.

27856183777921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1211138425150.

The product of its digits is 497871360, while the sum is 73.

The spelling of 27856183777921 in words is "twenty-seven trillion, eight hundred fifty-six billion, one hundred eighty-three million, seven hundred seventy-seven thousand, nine hundred twenty-one".