57716721549 has 6 divisors (see below), whose sum is σ = 83368597806. Its totient is φ = 38477814360.

The previous prime is 57716721523. The next prime is 57716721611. The reversal of 57716721549 is 94512761775.

57716721549 is a `hidden beast` number, since 5 + 7 + 71 + 6 + 7 + 21 + 549 = 666.

It can be written as a sum of positive squares in only one way, i.e., 57716699049 + 22500 = 240243^2 + 150^2 .

It is a de Polignac number, because none of the positive numbers 2^k-57716721549 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 57716721495 and 57716721504.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (57716721509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3206484522 + ... + 3206484539.

It is an arithmetic number, because the mean of its divisors is an integer number (13894766301).

Almost surely, 2^57716721549 is an apocalyptic number.

It is an amenable number.

57716721549 is a deficient number, since it is larger than the sum of its proper divisors (25651876257).

57716721549 is a wasteful number, since it uses less digits than its factorization.

57716721549 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6412969067 (or 6412969064 counting only the distinct ones).

The product of its digits is 3704400, while the sum is 54.

The spelling of 57716721549 in words is "fifty-seven billion, seven hundred sixteen million, seven hundred twenty-one thousand, five hundred forty-nine".