561409903 has 2 divisors, whose sum is σ = 561409904. Its totient is φ = 561409902.

The previous prime is 561409889. The next prime is 561409939. The reversal of 561409903 is 309904165.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 561409903 - 2¹⁷ = 561278831 is a prime.

It is a super-3 number, since 3×561409903³ (a number of 27 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (561409963) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 280704951 + 280704952.

It is an arithmetic number, because the mean of its divisors is an integer number (280704952).

Almost surely, 2^561409903 is an apocalyptic number.

561409903 is a deficient number, since it is larger than the sum of its proper divisors (1).

561409903 is an equidigital number, since it uses as much as digits as its factorization.

561409903 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 29160, while the sum is 37.

The square root of 561409903 is about 23694.0900437219. The cubic root of 561409903 is about 824.9482198294.

The spelling of 561409903 in words is "five hundred sixty-one million, four hundred nine thousand, nine hundred three".