672813209 has 2 divisors, whose sum is σ = 672813210. Its totient is φ = 672813208.

The previous prime is 672813179. The next prime is 672813257. The reversal of 672813209 is 902318276.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 499969600 + 172843609 = 22360^2 + 13147^2 .

It is a cyclic number.

It is not a de Polignac number, because 672813209 - 2¹² = 672809113 is a prime.

It is a super-2 number, since 2×672813209² = 905355228409755362, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (672813259) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 336406604 + 336406605.

It is an arithmetic number, because the mean of its divisors is an integer number (336406605).

Almost surely, 2^672813209 is an apocalyptic number.

It is an amenable number.

672813209 is a deficient number, since it is larger than the sum of its proper divisors (1).

672813209 is an equidigital number, since it uses as much as digits as its factorization.

672813209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36288, while the sum is 38.

The square root of 672813209 is about 25938.6431603505. The cubic root of 672813209 is about 876.2570054310.

The spelling of 672813209 in words is "six hundred seventy-two million, eight hundred thirteen thousand, two hundred nine".