561265218646109 has 2 divisors, whose sum is σ = 561265218646110. Its totient is φ = 561265218646108.

The previous prime is 561265218645983. The next prime is 561265218646189. The reversal of 561265218646109 is 901646812562165.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 421718958425209 + 139546260220900 = 20535797^2 + 11812970^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-561265218646109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (561265218646189) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 280632609323054 + 280632609323055.

It is an arithmetic number, because the mean of its divisors is an integer number (280632609323055).

Almost surely, 2^{561265218646109} is an apocalyptic number.

It is an amenable number.

561265218646109 is a deficient number, since it is larger than the sum of its proper divisors (1).

561265218646109 is an equidigital number, since it uses as much as digits as its factorization.

561265218646109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 37324800, while the sum is 62.

The spelling of 561265218646109 in words is "five hundred sixty-one trillion, two hundred sixty-five billion, two hundred eighteen million, six hundred forty-six thousand, one hundred nine".