6561464436 has 18 divisors (see below), whose sum is σ = 16585924082. Its totient is φ = 2187154800.

The previous prime is 6561464431. The next prime is 6561464453. The reversal of 6561464436 is 6344641656.

6561464436 is a `hidden beast` number, since 6 + 561 + 46 + 4 + 43 + 6 = 666.

It can be written as a sum of positive squares in only one way, i.e., 5206488336 + 1354976100 = 72156^2 + 36810^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a junction number, because it is equal to n+sod(n) for n = 6561464391 and 6561464400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6561464431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 91131415 + ... + 91131486.

Almost surely, 2^6561464436 is an apocalyptic number.

It is an amenable number.

6561464436 is an abundant number, since it is smaller than the sum of its proper divisors (10024459646).

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

6561464436 is a wasteful number, since it uses less digits than its factorization.

6561464436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 182262911 (or 182262906 counting only the distinct ones).

The product of its digits is 1244160, while the sum is 45.

The square root of 6561464436 is about 81002.8668381558. The cubic root of 6561464436 is about 1872.1196128096.

The spelling of 6561464436 in words is "six billion, five hundred sixty-one million, four hundred sixty-four thousand, four hundred thirty-six".