66528817 has 2 divisors, whose sum is σ = 66528818. Its totient is φ = 66528816.

The previous prime is 66528799. The next prime is 66528827. The reversal of 66528817 is 71882566.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 55711296 + 10817521 = 7464^2 + 3289^2 .

It is a cyclic number.

It is not a de Polignac number, because 66528817 - 2¹⁹ = 66004529 is a prime.

It is not a weakly prime, because it can be changed into another prime (66528827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33264408 + 33264409.

It is an arithmetic number, because the mean of its divisors is an integer number (33264409).

Almost surely, 2^66528817 is an apocalyptic number.

It is an amenable number.

66528817 is a deficient number, since it is larger than the sum of its proper divisors (1).

66528817 is an equidigital number, since it uses as much as digits as its factorization.

66528817 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 161280, while the sum is 43.

The square root of 66528817 is about 8156.5199074115. The cubic root of 66528817 is about 405.2004636820.

The spelling of 66528817 in words is "sixty-six million, five hundred twenty-eight thousand, eight hundred seventeen".