673553561 has 2 divisors, whose sum is σ = 673553562. Its totient is φ = 673553560.

The previous prime is 673553557. The next prime is 673553579. The reversal of 673553561 is 165355376.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 346667161 + 326886400 = 18619^2 + 18080^2 .

It is a cyclic number.

It is not a de Polignac number, because 673553561 - 2² = 673553557 is a prime.

It is not a weakly prime, because it can be changed into another prime (673553501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 336776780 + 336776781.

It is an arithmetic number, because the mean of its divisors is an integer number (336776781).

Almost surely, 2^673553561 is an apocalyptic number.

It is an amenable number.

673553561 is a deficient number, since it is larger than the sum of its proper divisors (1).

673553561 is an equidigital number, since it uses as much as digits as its factorization.

673553561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 283500, while the sum is 41.

The square root of 673553561 is about 25952.9104533576. The cubic root of 673553561 is about 876.5782936229.

The spelling of 673553561 in words is "six hundred seventy-three million, five hundred fifty-three thousand, five hundred sixty-one".