6693910821 has 16 divisors (see below), whose sum is σ = 10679744320. Its totient is φ = 4119329520.

The previous prime is 6693910801. The next prime is 6693910829. The reversal of 6693910821 is 1280193966.

It is a happy number.

6693910821 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 6693910821 - 2⁵ = 6693910789 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 (6693910829) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9535135 + ... + 9535836.

It is an arithmetic number, because the mean of its divisors is an integer number (667484020).

Almost surely, 2^6693910821 is an apocalyptic number.

It is an amenable number.

6693910821 is a deficient number, since it is larger than the sum of its proper divisors (3985833499).

6693910821 is a wasteful number, since it uses less digits than its factorization.

6693910821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19070993 (or 19070987 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 45.

The square root of 6693910821 is about 81816.3236829913. The cubic root of 6693910821 is about 1884.6323463584.

The spelling of 6693910821 in words is "six billion, six hundred ninety-three million, nine hundred ten thousand, eight hundred twenty-one".