561011 has 4 divisors (see below), whose sum is σ = 612024. Its totient is φ = 510000.

The previous prime is 560977. The next prime is 561019. The reversal of 561011 is 110165.

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 561011 - 2¹⁴ = 544627 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (561019) 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 3 ways as a sum of consecutive naturals, for example, 25490 + ... + 25511.

It is an arithmetic number, because the mean of its divisors is an integer number (153006).

2⁵⁶¹⁰¹¹ is an apocalyptic number.

561011 is a deficient number, since it is larger than the sum of its proper divisors (51013).

561011 is a wasteful number, since it uses less digits than its factorization.

561011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51012.

The product of its (nonzero) digits is 30, while the sum is 14.

The square root of 561011 is about 749.0066755377. The cubic root of 561011 is about 82.4752787883.

Adding to 561011 its reverse (110165), we get a palindrome (671176).

It can be divided in two parts, 56 and 1011, that multiplied together give a triangular number (56616 = T₃₃₆).

The spelling of 561011 in words is "five hundred sixty-one thousand, eleven".