6561723 has 16 divisors (see below), whose sum is σ = 10044416. Its totient is φ = 3732480.

The previous prime is 6561721. The next prime is 6561761. The reversal of 6561723 is 3271656.

It is not a de Polignac number, because 6561723 - 2¹ = 6561721 is a prime.

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6561721) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5115 + ... + 6267.

It is an arithmetic number, because the mean of its divisors is an integer number (627776).

Almost surely, 2^6561723 is an apocalyptic number.

6561723 is a deficient number, since it is larger than the sum of its proper divisors (3482693).

6561723 is a wasteful number, since it uses less digits than its factorization.

6561723 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1434.

The product of its digits is 7560, while the sum is 30.

The square root of 6561723 is about 2561.5860321293. The cubic root of 6561723 is about 187.2144203681.

The spelling of 6561723 in words is "six million, five hundred sixty-one thousand, seven hundred twenty-three".