6621843439 has 4 divisors (see below), whose sum is σ = 6623181040. Its totient is φ = 6620505840.

The previous prime is 6621843427. The next prime is 6621843461. The reversal of 6621843439 is 9343481266.

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 6621843439 - 2⁵ = 6621843407 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 (6621843139) 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, 661347 + ... + 671284.

It is an arithmetic number, because the mean of its divisors is an integer number (1655795260).

Almost surely, 2^6621843439 is an apocalyptic number.

6621843439 is a deficient number, since it is larger than the sum of its proper divisors (1337601).

6621843439 is a wasteful number, since it uses less digits than its factorization.

6621843439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1337600.

The product of its digits is 746496, while the sum is 46.

The square root of 6621843439 is about 81374.7100701440. The cubic root of 6621843439 is about 1877.8445417962.

The spelling of 6621843439 in words is "six billion, six hundred twenty-one million, eight hundred forty-three thousand, four hundred thirty-nine".