6421439849 has 4 divisors (see below), whose sum is σ = 7005207120. Its totient is φ = 5837672580.

The previous prime is 6421439839. The next prime is 6421439891. The reversal of 6421439849 is 9489341246.

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 6421439849 - 2¹² = 6421435753 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6421439797 and 6421439806.

It is not an unprimeable number, because it can be changed into a prime (6421439839) 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, 291883619 + ... + 291883640.

It is an arithmetic number, because the mean of its divisors is an integer number (1751301780).

Almost surely, 2^6421439849 is an apocalyptic number.

It is an amenable number.

6421439849 is a deficient number, since it is larger than the sum of its proper divisors (583767271).

6421439849 is a wasteful number, since it uses less digits than its factorization.

6421439849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 583767270.

The product of its digits is 1492992, while the sum is 50.

The square root of 6421439849 is about 80133.8870204110. The cubic root of 6421439849 is about 1858.7064510660.

The spelling of 6421439849 in words is "six billion, four hundred twenty-one million, four hundred thirty-nine thousand, eight hundred forty-nine".