561506965 has 8 divisors (see below), whose sum is σ = 677704248. Its totient is φ = 446608320.

The previous prime is 561506909. The next prime is 561506971. The reversal of 561506965 is 569605165.

It can be written as a sum of positive squares in 4 ways, for example, as 21362884 + 540144081 = 4622^2 + 23241^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 561506965 - 2⁹ = 561506453 is a prime.

It is a super-2 number, since 2×561506965² = 630580143487022450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 323706 + ... + 325435.

It is an arithmetic number, because the mean of its divisors is an integer number (84713031).

Almost surely, 2^561506965 is an apocalyptic number.

It is an amenable number.

561506965 is a deficient number, since it is larger than the sum of its proper divisors (116197283).

561506965 is a wasteful number, since it uses less digits than its factorization.

561506965 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 649319.

The product of its (nonzero) digits is 243000, while the sum is 43.

The square root of 561506965 is about 23696.1381874769. The cubic root of 561506965 is about 824.9957587783.

The spelling of 561506965 in words is "five hundred sixty-one million, five hundred six thousand, nine hundred sixty-five".