27144471821 has 4 divisors (see below), whose sum is σ = 28324666272. Its totient is φ = 25964277372.

The previous prime is 27144471797. The next prime is 27144471833. The reversal of 27144471821 is 12817444172.

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 a de Polignac number, because none of the positive numbers 2^k-27144471821 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 (27144471881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 590097191 + ... + 590097236.

It is an arithmetic number, because the mean of its divisors is an integer number (7081166568).

Almost surely, 2^27144471821 is an apocalyptic number.

It is an amenable number.

27144471821 is a deficient number, since it is larger than the sum of its proper divisors (1180194451).

27144471821 is a wasteful number, since it uses less digits than its factorization.

27144471821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1180194450.

The product of its digits is 100352, while the sum is 41.

The spelling of 27144471821 in words is "twenty-seven billion, one hundred forty-four million, four hundred seventy-one thousand, eight hundred twenty-one".