561670643 has 4 divisors (see below), whose sum is σ = 567461160. Its totient is φ = 555880128.

The previous prime is 561670631. The next prime is 561670657. The reversal of 561670643 is 346076165.

It is a happy number.

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 561670643 - 2²⁰ = 560622067 is a prime.

It is a super-2 number, since 2×561670643² = 630947822416066898, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 561670597 and 561670606.

It is not an unprimeable number, because it can be changed into a prime (561670243) 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, 2895113 + ... + 2895306.

It is an arithmetic number, because the mean of its divisors is an integer number (141865290).

Almost surely, 2^561670643 is an apocalyptic number.

561670643 is a deficient number, since it is larger than the sum of its proper divisors (5790517).

561670643 is an equidigital number, since it uses as much as digits as its factorization.

561670643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5790516.

The product of its (nonzero) digits is 90720, while the sum is 38.

The square root of 561670643 is about 23699.5916209541. The cubic root of 561670643 is about 825.0759124515.

The spelling of 561670643 in words is "five hundred sixty-one million, six hundred seventy thousand, six hundred forty-three".