561536643 has 8 divisors (see below), whose sum is σ = 762842448. Its totient is φ = 367294304.

The previous prime is 561536641. The next prime is 561536681. The reversal of 561536643 is 346635165.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 561536643 - 2¹ = 561536641 is a prime.

It is not an unprimeable number, because it can be changed into a prime (561536641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1765680 + ... + 1765997.

It is an arithmetic number, because the mean of its divisors is an integer number (95355306).

Almost surely, 2^561536643 is an apocalyptic number.

561536643 is a gapful number since it is divisible by the number (53) formed by its first and last digit.

561536643 is a deficient number, since it is larger than the sum of its proper divisors (201305805).

561536643 is a wasteful number, since it uses less digits than its factorization.

561536643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3531733.

The product of its digits is 194400, while the sum is 39.

The square root of 561536643 is about 23696.7643993858. The cubic root of 561536643 is about 825.0102933518.

The spelling of 561536643 in words is "five hundred sixty-one million, five hundred thirty-six thousand, six hundred forty-three".