72216449 has 2 divisors, whose sum is σ = 72216450. Its totient is φ = 72216448.

The previous prime is 72216437. The next prime is 72216499. The reversal of 72216449 is 94461227.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 57532225 + 14684224 = 7585^2 + 3832^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72216449 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (72216499) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36108224 + 36108225.

It is an arithmetic number, because the mean of its divisors is an integer number (36108225).

Almost surely, 2^72216449 is an apocalyptic number.

It is an amenable number.

72216449 is a deficient number, since it is larger than the sum of its proper divisors (1).

72216449 is an equidigital number, since it uses as much as digits as its factorization.

72216449 is an evil number, because the sum of its binary digits is even.

The product of its digits is 24192, while the sum is 35.

The square root of 72216449 is about 8498.0261825909. The cubic root of 72216449 is about 416.4332290988.

It can be divided in two parts, 722 and 16449, that added together give a palindrome (17171).

The spelling of 72216449 in words is "seventy-two million, two hundred sixteen thousand, four hundred forty-nine".