66213523 has 2 divisors, whose sum is σ = 66213524. Its totient is φ = 66213522.

The previous prime is 66213509. The next prime is 66213529. The reversal of 66213523 is 32531266.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66213523 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66213491 and 66213500.

It is not a weakly prime, because it can be changed into another prime (66213529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33106761 + 33106762.

It is an arithmetic number, because the mean of its divisors is an integer number (33106762).

Almost surely, 2^66213523 is an apocalyptic number.

66213523 is a deficient number, since it is larger than the sum of its proper divisors (1).

66213523 is an equidigital number, since it uses as much as digits as its factorization.

66213523 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6480, while the sum is 28.

The square root of 66213523 is about 8137.1692252281. The cubic root of 66213523 is about 404.5593398470.

Adding to 66213523 its reverse (32531266), we get a palindrome (98744789).

The spelling of 66213523 in words is "sixty-six million, two hundred thirteen thousand, five hundred twenty-three".