561243 has 4 divisors (see below), whose sum is σ = 748328. Its totient is φ = 374160.

The previous prime is 561229. The next prime is 561251. The reversal of 561243 is 342165.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 561243 - 2¹³ = 553051 is a prime.

It is a D-number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (561343) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 93538 + ... + 93543.

It is an arithmetic number, because the mean of its divisors is an integer number (187082).

2⁵⁶¹²⁴³ is an apocalyptic number.

561243 is a deficient number, since it is larger than the sum of its proper divisors (187085).

561243 is a wasteful number, since it uses less digits than its factorization.

561243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187084.

The product of its digits is 720, while the sum is 21.

The square root of 561243 is about 749.1615313135. The cubic root of 561243 is about 82.4866461398.

The spelling of 561243 in words is "five hundred sixty-one thousand, two hundred forty-three".