6709448557821 has 4 divisors (see below), whose sum is σ = 8945931410432. Its totient is φ = 4472965705212.

The previous prime is 6709448557793. The next prime is 6709448557829. The reversal of 6709448557821 is 1287558449076.

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 not a de Polignac number, because 6709448557821 - 2⁵ = 6709448557789 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 (6709448557829) 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, 1118241426301 + ... + 1118241426306.

It is an arithmetic number, because the mean of its divisors is an integer number (2236482852608).

Almost surely, 2^{6709448557821} is an apocalyptic number.

It is an amenable number.

6709448557821 is a deficient number, since it is larger than the sum of its proper divisors (2236482852611).

6709448557821 is a wasteful number, since it uses less digits than its factorization.

6709448557821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2236482852610.

The product of its (nonzero) digits is 135475200, while the sum is 66.

The spelling of 6709448557821 in words is "six trillion, seven hundred nine billion, four hundred forty-eight million, five hundred fifty-seven thousand, eight hundred twenty-one".