72517729 has 2 divisors, whose sum is σ = 72517730. Its totient is φ = 72517728.

The previous prime is 72517673. The next prime is 72517747. The reversal of 72517729 is 92771527.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 42837025 + 29680704 = 6545^2 + 5448^2 .

It is an emirp because it is prime and its reverse (92771527) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 72517729 - 2²¹ = 70420577 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 72517691 and 72517700.

It is not a weakly prime, because it can be changed into another prime (72517759) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36258864 + 36258865.

It is an arithmetic number, because the mean of its divisors is an integer number (36258865).

Almost surely, 2^72517729 is an apocalyptic number.

It is an amenable number.

72517729 is a deficient number, since it is larger than the sum of its proper divisors (1).

72517729 is an equidigital number, since it uses as much as digits as its factorization.

72517729 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 61740, while the sum is 40.

The square root of 72517729 is about 8515.7342020521. The cubic root of 72517729 is about 417.0115319421.

The spelling of 72517729 in words is "seventy-two million, five hundred seventeen thousand, seven hundred twenty-nine".