27821421847 has 4 divisors (see below), whose sum is σ = 27824815080. Its totient is φ = 27818028616.

The previous prime is 27821421839. The next prime is 27821421869. The reversal of 27821421847 is 74812412872.

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

It is a cyclic number.

It is not a de Polignac number, because 27821421847 - 2³ = 27821421839 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 27821421797 and 27821421806.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27821421827) 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, 1684288 + ... + 1700725.

It is an arithmetic number, because the mean of its divisors is an integer number (6956203770).

Almost surely, 2^27821421847 is an apocalyptic number.

27821421847 is a deficient number, since it is larger than the sum of its proper divisors (3393233).

27821421847 is an equidigital number, since it uses as much as digits as its factorization.

27821421847 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3393232.

The product of its digits is 401408, while the sum is 46.

The spelling of 27821421847 in words is "twenty-seven billion, eight hundred twenty-one million, four hundred twenty-one thousand, eight hundred forty-seven".