72597509 has 2 divisors, whose sum is σ = 72597510. Its totient is φ = 72597508.

The previous prime is 72597479. The next prime is 72597521. The reversal of 72597509 is 90579527.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65966884 + 6630625 = 8122^2 + 2575^2 .

It is a cyclic number.

It is not a de Polignac number, because 72597509 - 2¹⁶ = 72531973 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 72597509.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72597559) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36298754 + 36298755.

It is an arithmetic number, because the mean of its divisors is an integer number (36298755).

Almost surely, 2^72597509 is an apocalyptic number.

It is an amenable number.

72597509 is a deficient number, since it is larger than the sum of its proper divisors (1).

72597509 is an equidigital number, since it uses as much as digits as its factorization.

72597509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 198450, while the sum is 44.

The square root of 72597509 is about 8520.4171846219. The cubic root of 72597509 is about 417.1644002481.

The spelling of 72597509 in words is "seventy-two million, five hundred ninety-seven thousand, five hundred nine".