561440121 has 24 divisors (see below), whose sum is σ = 841985760. Its totient is φ = 332344320.

The previous prime is 561440119. The next prime is 561440129. The reversal of 561440121 is 121044165.

It is a happy number.

It is not a de Polignac number, because 561440121 - 2¹ = 561440119 is a prime.

It is a super-3 number, since 3×561440121³ (a number of 27 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 561440091 and 561440100.

It is not an unprimeable number, because it can be changed into a prime (561440129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2376 + ... + 33593.

It is an arithmetic number, because the mean of its divisors is an integer number (35082740).

Almost surely, 2^561440121 is an apocalyptic number.

It is an amenable number.

561440121 is a deficient number, since it is larger than the sum of its proper divisors (280545639).

561440121 is a wasteful number, since it uses less digits than its factorization.

561440121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36037 (or 36026 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 24.

The square root of 561440121 is about 23694.7277047026. The cubic root of 561440121 is about 824.9630205647.

Adding to 561440121 its reverse (121044165), we get a palindrome (682484286).

The spelling of 561440121 in words is "five hundred sixty-one million, four hundred forty thousand, one hundred twenty-one".