561723647 has 4 divisors (see below), whose sum is σ = 562061880. Its totient is φ = 561385416.

The previous prime is 561723629. The next prime is 561723653. The reversal of 561723647 is 746327165.

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 561723647 - 2⁶ = 561723583 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561723697) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 166613 + ... + 169950.

It is an arithmetic number, because the mean of its divisors is an integer number (140515470).

Almost surely, 2^561723647 is an apocalyptic number.

561723647 is a deficient number, since it is larger than the sum of its proper divisors (338233).

561723647 is a wasteful number, since it uses less digits than its factorization.

561723647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 338232.

The product of its digits is 211680, while the sum is 41.

The square root of 561723647 is about 23700.7098416904. The cubic root of 561723647 is about 825.1018653527.

The spelling of 561723647 in words is "five hundred sixty-one million, seven hundred twenty-three thousand, six hundred forty-seven".