72209609 has 2 divisors, whose sum is σ = 72209610. Its totient is φ = 72209608.

The previous prime is 72209603. The next prime is 72209639. The reversal of 72209609 is 90690227.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 71910400 + 299209 = 8480^2 + 547^2 .

It is an emirp because it is prime and its reverse (90690227) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 72209609 - 2⁴ = 72209593 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (72209603) 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, 36104804 + 36104805.

It is an arithmetic number, because the mean of its divisors is an integer number (36104805).

Almost surely, 2^72209609 is an apocalyptic number.

It is an amenable number.

72209609 is a deficient number, since it is larger than the sum of its proper divisors (1).

72209609 is an equidigital number, since it uses as much as digits as its factorization.

72209609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13608, while the sum is 35.

The square root of 72209609 is about 8497.6237266662. The cubic root of 72209609 is about 416.4200811560.

The spelling of 72209609 in words is "seventy-two million, two hundred nine thousand, six hundred nine".