561511505 has 4 divisors (see below), whose sum is σ = 673813812. Its totient is φ = 449209200.

The previous prime is 561511499. The next prime is 561511553. The reversal of 561511505 is 505115165.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 261113281 + 300398224 = 16159^2 + 17332^2 .

It is not a de Polignac number, because 561511505 - 2¹⁸ = 561249361 is a prime.

It is a Duffinian 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 3 ways as a sum of consecutive naturals, for example, 56151146 + ... + 56151155.

It is an arithmetic number, because the mean of its divisors is an integer number (168453453).

Almost surely, 2^561511505 is an apocalyptic number.

It is an amenable number.

561511505 is a deficient number, since it is larger than the sum of its proper divisors (112302307).

561511505 is a wasteful number, since it uses less digits than its factorization.

561511505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112302306.

The product of its (nonzero) digits is 3750, while the sum is 29.

The square root of 561511505 is about 23696.2339834835. The cubic root of 561511505 is about 824.9979822418.

The spelling of 561511505 in words is "five hundred sixty-one million, five hundred eleven thousand, five hundred five".