655536521 has 4 divisors (see below), whose sum is σ = 655588500. Its totient is φ = 655484544.

The previous prime is 655536493. The next prime is 655536523. The reversal of 655536521 is 125635556.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 91948921 + 563587600 = 9589^2 + 23740^2 .

It is a cyclic number.

It is not a de Polignac number, because 655536521 - 2¹⁰ = 655535497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (655536523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6305 + ... + 36753.

It is an arithmetic number, because the mean of its divisors is an integer number (163897125).

Almost surely, 2^655536521 is an apocalyptic number.

It is an amenable number.

655536521 is a deficient number, since it is larger than the sum of its proper divisors (51979).

655536521 is a wasteful number, since it uses less digits than its factorization.

655536521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51978.

The product of its digits is 135000, while the sum is 38.

The square root of 655536521 is about 25603.4474436549. The cubic root of 655536521 is about 868.6916172418.

The spelling of 655536521 in words is "six hundred fifty-five million, five hundred thirty-six thousand, five hundred twenty-one".