72205565 has 12 divisors (see below), whose sum is σ = 87986556. Its totient is φ = 56884608.

The previous prime is 72205561. The next prime is 72205571. The reversal of 72205565 is 56550227.

It can be written as a sum of positive squares in 2 ways, for example, as 47623801 + 24581764 = 6901^2 + 4958^2 .

It is not a de Polignac number, because 72205565 - 2² = 72205561 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72205561) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20837 + ... + 24053.

It is an arithmetic number, because the mean of its divisors is an integer number (7332213).

Almost surely, 2^72205565 is an apocalyptic number.

It is an amenable number.

72205565 is a deficient number, since it is larger than the sum of its proper divisors (15780991).

72205565 is an equidigital number, since it uses as much as digits as its factorization.

72205565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3356 (or 3289 counting only the distinct ones).

The product of its (nonzero) digits is 21000, while the sum is 32.

The square root of 72205565 is about 8497.3857744603. The cubic root of 72205565 is about 416.4123073326.

The spelling of 72205565 in words is "seventy-two million, two hundred five thousand, five hundred sixty-five".