561629161 has 2 divisors, whose sum is σ = 561629162. Its totient is φ = 561629160.

The previous prime is 561629059. The next prime is 561629213. The reversal of 561629161 is 161926165.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 322741225 + 238887936 = 17965^2 + 15456^2 .

It is a cyclic number.

It is not a de Polignac number, because 561629161 - 2²¹ = 559532009 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 561629161.

It is not a weakly prime, because it can be changed into another prime (561621161) 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 as a sum of consecutive naturals, namely, 280814580 + 280814581.

It is an arithmetic number, because the mean of its divisors is an integer number (280814581).

Almost surely, 2^561629161 is an apocalyptic number.

It is an amenable number.

561629161 is a deficient number, since it is larger than the sum of its proper divisors (1).

561629161 is an equidigital number, since it uses as much as digits as its factorization.

561629161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 19440, while the sum is 37.

The square root of 561629161 is about 23698.7164420354. The cubic root of 561629161 is about 825.0556000483.

The spelling of 561629161 in words is "five hundred sixty-one million, six hundred twenty-nine thousand, one hundred sixty-one".