5781721768 has 8 divisors (see below), whose sum is σ = 10840728330. Its totient is φ = 2890860880.

The previous prime is 5781721741. The next prime is 5781721769. The reversal of 5781721768 is 8671271875.

It can be written as a sum of positive squares in only one way, i.e., 5449097124 + 332624644 = 73818^2 + 18238^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (5781721769) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 361357603 + ... + 361357618.

Almost surely, 2^5781721768 is an apocalyptic number.

It is an amenable number.

5781721768 is a deficient number, since it is larger than the sum of its proper divisors (5059006562).

5781721768 is a wasteful number, since it uses less digits than its factorization.

5781721768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 722715227 (or 722715223 counting only the distinct ones).

The product of its digits is 1317120, while the sum is 52.

The square root of 5781721768 is about 76037.6338926982. The cubic root of 5781721768 is about 1794.8124061215.

The spelling of 5781721768 in words is "five billion, seven hundred eighty-one million, seven hundred twenty-one thousand, seven hundred sixty-eight".