6505556161 has 4 divisors (see below), whose sum is σ = 7005983572. Its totient is φ = 6005128752.

The previous prime is 6505556149. The next prime is 6505556171. The reversal of 6505556161 is 1616555056.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4219281936 + 2286274225 = 64956^2 + 47815^2 .

It is a cyclic number.

It is not a de Polignac number, because 6505556161 - 2¹³ = 6505547969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6505556171) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 250213686 + ... + 250213711.

It is an arithmetic number, because the mean of its divisors is an integer number (1751495893).

Almost surely, 2^6505556161 is an apocalyptic number.

It is an amenable number.

6505556161 is a deficient number, since it is larger than the sum of its proper divisors (500427411).

6505556161 is a wasteful number, since it uses less digits than its factorization.

6505556161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 500427410.

The product of its (nonzero) digits is 135000, while the sum is 40.

The square root of 6505556161 is about 80657.0279702891. The cubic root of 6505556161 is about 1866.7871816573.

The spelling of 6505556161 in words is "six billion, five hundred five million, five hundred fifty-six thousand, one hundred sixty-one".