561219817 has 2 divisors, whose sum is σ = 561219818. Its totient is φ = 561219816.

The previous prime is 561219781. The next prime is 561219823. The reversal of 561219817 is 718912165.

It is a happy number.

Together with previous prime (561219781) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 291077721 + 270142096 = 17061^2 + 16436^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-561219817 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 561219817.

It is not a weakly prime, because it can be changed into another prime (561219887) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 280609908 + 280609909.

It is an arithmetic number, because the mean of its divisors is an integer number (280609909).

Almost surely, 2^561219817 is an apocalyptic number.

It is an amenable number.

561219817 is a deficient number, since it is larger than the sum of its proper divisors (1).

561219817 is an equidigital number, since it uses as much as digits as its factorization.

561219817 is an evil number, because the sum of its binary digits is even.

The product of its digits is 30240, while the sum is 40.

The square root of 561219817 is about 23690.0784506932. The cubic root of 561219817 is about 824.8551037848.

The spelling of 561219817 in words is "five hundred sixty-one million, two hundred nineteen thousand, eight hundred seventeen".