561736 has 24 divisors (see below), whose sum is σ = 1226070. Its totient is φ = 240576.

The previous prime is 561733. The next prime is 561761. The reversal of 561736 is 637165.

It can be written as a sum of positive squares in only one way, i.e., 396900 + 164836 = 630^2 + 406^2 .

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a nialpdrome in base 8.

It is not an unprimeable number, because it can be changed into a prime (561733) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 325 + ... + 1108.

2⁵⁶¹⁷³⁶ is an apocalyptic number.

561736 is a gapful number since it is divisible by the number (56) formed by its first and last digit.

It is an amenable number.

561736 is an abundant number, since it is smaller than the sum of its proper divisors (664334).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

561736 is a wasteful number, since it uses less digits than its factorization.

561736 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1453 (or 1442 counting only the distinct ones).

The product of its digits is 3780, while the sum is 28.

The square root of 561736 is about 749.4904936022. The cubic root of 561736 is about 82.5107913646.

Adding to 561736 its product of digits (3780), we get a triangular number (565516 = T₁₀₆₃).

The spelling of 561736 in words is "five hundred sixty-one thousand, seven hundred thirty-six".