6561655212 has 48 divisors (see below), whose sum is σ = 17580722432. Its totient is φ = 1865868480.

The previous prime is 6561655193. The next prime is 6561655213. The reversal of 6561655212 is 2125561656.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (6561655213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 167383 + ... + 202830.

Almost surely, 2^6561655212 is an apocalyptic number.

It is an amenable number.

6561655212 is an abundant number, since it is smaller than the sum of its proper divisors (11019067220).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6561655212 is a wasteful number, since it uses less digits than its factorization.

6561655212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 370438 (or 370436 counting only the distinct ones).

The product of its digits is 108000, while the sum is 39.

The square root of 6561655212 is about 81004.0444175474. The cubic root of 6561655212 is about 1872.1377567282.

The spelling of 6561655212 in words is "six billion, five hundred sixty-one million, six hundred fifty-five thousand, two hundred twelve".