6840447849 has 27 divisors (see below), whose sum is σ = 10435242909. Its totient is φ = 4317305400.

The previous prime is 6840447839. The next prime is 6840447883. The reversal of 6840447849 is 9487440486.

The square root of 6840447849 is 82707.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 6840447849 - 2⁷ = 6840447721 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 6840447795 and 6840447804.

It is not an unprimeable number, because it can be changed into a prime (6840447839) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 4713574 + ... + 4715024.

Almost surely, 2^6840447849 is an apocalyptic number.

6840447849 is the 82707-th square number.

6840447849 is the 41354-th centered octagonal number.

It is an amenable number.

6840447849 is a deficient number, since it is larger than the sum of its proper divisors (3594795060).

6840447849 is an equidigital number, since it uses as much as digits as its factorization.

6840447849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2946 (or 1473 counting only the distinct ones).

The product of its (nonzero) digits is 6193152, while the sum is 54.

The cubic root of 6840447849 is about 1898.2854198768.

The spelling of 6840447849 in words is "six billion, eight hundred forty million, four hundred forty-seven thousand, eight hundred forty-nine".