561551615 has 4 divisors (see below), whose sum is σ = 673861944. Its totient is φ = 449241288.

The previous prime is 561551611. The next prime is 561551657. The reversal of 561551615 is 516155165.

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

It is a cyclic number.

It is not a de Polignac number, because 561551615 - 2² = 561551611 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561551611) 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 3 ways as a sum of consecutive naturals, for example, 56155157 + ... + 56155166.

It is an arithmetic number, because the mean of its divisors is an integer number (168465486).

Almost surely, 2^561551615 is an apocalyptic number.

561551615 is a deficient number, since it is larger than the sum of its proper divisors (112310329).

561551615 is a wasteful number, since it uses less digits than its factorization.

561551615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112310328.

The product of its digits is 22500, while the sum is 35.

The square root of 561551615 is about 23697.0803053878. The cubic root of 561551615 is about 825.0176255800.

The spelling of 561551615 in words is "five hundred sixty-one million, five hundred fifty-one thousand, six hundred fifteen".