72564509 has 2 divisors, whose sum is σ = 72564510. Its totient is φ = 72564508.

The previous prime is 72564487. The next prime is 72564523. The reversal of 72564509 is 90546527.

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., 49042009 + 23522500 = 7003^2 + 4850^2 .

It is a cyclic number.

It is not a de Polignac number, because 72564509 - 2¹² = 72560413 is a prime.

It is a super-2 number, since 2×72564509² = 10531215932822162, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72564589) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36282254 + 36282255.

It is an arithmetic number, because the mean of its divisors is an integer number (36282255).

Almost surely, 2^72564509 is an apocalyptic number.

It is an amenable number.

72564509 is a deficient number, since it is larger than the sum of its proper divisors (1).

72564509 is an equidigital number, since it uses as much as digits as its factorization.

72564509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 75600, while the sum is 38.

The square root of 72564509 is about 8518.4804396089. The cubic root of 72564509 is about 417.1011817722.

The spelling of 72564509 in words is "seventy-two million, five hundred sixty-four thousand, five hundred nine".