6693546921721 has 9 divisors (see below), whose sum is σ = 7357401038533. Its totient is φ = 6085016784220.

The previous prime is 6693546921679. The next prime is 6693546921779. The reversal of 6693546921721 is 1271296453966.

It is a happy number.

The square root of 6693546921721 is 2587189.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 6693546921721 - 2¹¹ = 6693546919673 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6693546921721.

It is not an unprimeable number, because it can be changed into a prime (6693546921421) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 28341480 + ... + 28576678.

Almost surely, 2^{6693546921721} is an apocalyptic number.

6693546921721 is the 2587189-th square number.

6693546921721 is the 1293595-th centered octagonal number.

It is an amenable number.

6693546921721 is a deficient number, since it is larger than the sum of its proper divisors (663854116812).

6693546921721 is an frugal number, since it uses more digits than its factorization.

6693546921721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 470420 (or 235210 counting only the distinct ones).

The product of its digits is 29393280, while the sum is 61.

The spelling of 6693546921721 in words is "six trillion, six hundred ninety-three billion, five hundred forty-six million, nine hundred twenty-one thousand, seven hundred twenty-one".