72309073 has 2 divisors, whose sum is σ = 72309074. Its totient is φ = 72309072.

The previous prime is 72309071. The next prime is 72309091. The reversal of 72309073 is 37090327.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 39727809 + 32581264 = 6303^2 + 5708^2 .

It is an emirp because it is prime and its reverse (37090327) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 72309073 - 2¹ = 72309071 is a prime.

Together with 72309071, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (72309071) 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, 36154536 + 36154537.

It is an arithmetic number, because the mean of its divisors is an integer number (36154537).

Almost surely, 2^72309073 is an apocalyptic number.

It is an amenable number.

72309073 is a deficient number, since it is larger than the sum of its proper divisors (1).

72309073 is an equidigital number, since it uses as much as digits as its factorization.

72309073 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7938, while the sum is 31.

The square root of 72309073 is about 8503.4741723604. The cubic root of 72309073 is about 416.6111905519.

The spelling of 72309073 in words is "seventy-two million, three hundred nine thousand, seventy-three".