6561447 has 4 divisors (see below), whose sum is σ = 8748600. Its totient is φ = 4374296.

The previous prime is 6561437. The next prime is 6561461. The reversal of 6561447 is 7441656.

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

It is a cyclic number.

It is not a de Polignac number, because 6561447 - 2⁶ = 6561383 is a prime.

It is a D-number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6561427) 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, 1093572 + ... + 1093577.

It is an arithmetic number, because the mean of its divisors is an integer number (2187150).

Almost surely, 2^6561447 is an apocalyptic number.

6561447 is a deficient number, since it is larger than the sum of its proper divisors (2187153).

6561447 is a wasteful number, since it uses less digits than its factorization.

6561447 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2187152.

The product of its digits is 20160, while the sum is 33.

The square root of 6561447 is about 2561.5321586894. The cubic root of 6561447 is about 187.2117954526.

The spelling of 6561447 in words is "six million, five hundred sixty-one thousand, four hundred forty-seven".