673506409 has 2 divisors, whose sum is σ = 673506410. Its totient is φ = 673506408.

The previous prime is 673506359. The next prime is 673506413. The reversal of 673506409 is 904605376.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 428490000 + 245016409 = 20700^2 + 15653^2 .

It is a cyclic number.

It is not a de Polignac number, because 673506409 - 2⁹ = 673505897 is a prime.

It is a super-2 number, since 2×673506409² = 907221765928150562, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (673506439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 336753204 + 336753205.

It is an arithmetic number, because the mean of its divisors is an integer number (336753205).

Almost surely, 2^673506409 is an apocalyptic number.

It is an amenable number.

673506409 is a deficient number, since it is larger than the sum of its proper divisors (1).

673506409 is an equidigital number, since it uses as much as digits as its factorization.

673506409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 136080, while the sum is 40.

The square root of 673506409 is about 25952.0020229654. The cubic root of 673506409 is about 876.5578382419.

The spelling of 673506409 in words is "six hundred seventy-three million, five hundred six thousand, four hundred nine".