7218529 has 2 divisors, whose sum is σ = 7218530. Its totient is φ = 7218528.

The previous prime is 7218503. The next prime is 7218551. The reversal of 7218529 is 9258127.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6640929 + 577600 = 2577^2 + 760^2 .

It is a cyclic number.

It is not a de Polignac number, because 7218529 - 2¹³ = 7210337 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a junction number, because it is equal to n+sod(n) for n = 7218494 and 7218503.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7218559) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3609264 + 3609265.

It is an arithmetic number, because the mean of its divisors is an integer number (3609265).

Almost surely, 2^7218529 is an apocalyptic number.

It is an amenable number.

7218529 is a deficient number, since it is larger than the sum of its proper divisors (1).

7218529 is an equidigital number, since it uses as much as digits as its factorization.

7218529 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10080, while the sum is 34.

The square root of 7218529 is about 2686.7320298087. The cubic root of 7218529 is about 193.2633790380.

The spelling of 7218529 in words is "seven million, two hundred eighteen thousand, five hundred twenty-nine".