6506055155521 has 4 divisors (see below), whose sum is σ = 6521080687492. Its totient is φ = 6491029623552.

The previous prime is 6506055155513. The next prime is 6506055155591. The reversal of 6506055155521 is 1255515506056.

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 2028599155521 + 4477456000000 = 1424289^2 + 2116000^2 .

It is a cyclic number.

It is not a de Polignac number, because 6506055155521 - 2³ = 6506055155513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6506055155591) 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, 7512765336 + ... + 7512766201.

It is an arithmetic number, because the mean of its divisors is an integer number (1630270171873).

Almost surely, 2^{6506055155521} is an apocalyptic number.

It is an amenable number.

6506055155521 is a deficient number, since it is larger than the sum of its proper divisors (15025531971).

6506055155521 is a wasteful number, since it uses less digits than its factorization.

6506055155521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15025531970.

The product of its (nonzero) digits is 1125000, while the sum is 46.

The spelling of 6506055155521 in words is "six trillion, five hundred six billion, fifty-five million, one hundred fifty-five thousand, five hundred twenty-one".