27921331439 has 4 divisors (see below), whose sum is σ = 27924832656. Its totient is φ = 27917830224.

The previous prime is 27921331397. The next prime is 27921331453. The reversal of 27921331439 is 93413312972.

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-27921331439 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 27921331439.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27921331469) 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, 1738619 + ... + 1754604.

It is an arithmetic number, because the mean of its divisors is an integer number (6981208164).

Almost surely, 2^27921331439 is an apocalyptic number.

27921331439 is a deficient number, since it is larger than the sum of its proper divisors (3501217).

27921331439 is an equidigital number, since it uses as much as digits as its factorization.

27921331439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3501216.

The product of its digits is 244944, while the sum is 44.

The spelling of 27921331439 in words is "twenty-seven billion, nine hundred twenty-one million, three hundred thirty-one thousand, four hundred thirty-nine".