6720661717 has 16 divisors (see below), whose sum is σ = 8473161600. Its totient is φ = 5178032640.

The previous prime is 6720661699. The next prime is 6720661747. The reversal of 6720661717 is 7171660276.

It is a de Polignac number, because none of the positive numbers 2^k-6720661717 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 (6720661747) 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, 483492 + ... + 497197.

It is an arithmetic number, because the mean of its divisors is an integer number (529572600).

Almost surely, 2^6720661717 is an apocalyptic number.

It is an amenable number.

6720661717 is a deficient number, since it is larger than the sum of its proper divisors (1752499883).

6720661717 is a wasteful number, since it uses less digits than its factorization.

6720661717 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 980796.

The product of its (nonzero) digits is 148176, while the sum is 43.

The square root of 6720661717 is about 81979.6420887527. The cubic root of 6720661717 is about 1887.1395301394.

The spelling of 6720661717 in words is "six billion, seven hundred twenty million, six hundred sixty-one thousand, seven hundred seventeen".