66506497 has 2 divisors, whose sum is σ = 66506498. Its totient is φ = 66506496.

The previous prime is 66506491. The next prime is 66506507. The reversal of 66506497 is 79460566.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38638656 + 27867841 = 6216^2 + 5279^2 .

It is a cyclic number.

It is not a de Polignac number, because 66506497 - 2⁷ = 66506369 is a prime.

It is a super-2 number, since 2×66506497² = 8846228286422018, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (66506491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33253248 + 33253249.

It is an arithmetic number, because the mean of its divisors is an integer number (33253249).

Almost surely, 2^66506497 is an apocalyptic number.

It is an amenable number.

66506497 is a deficient number, since it is larger than the sum of its proper divisors (1).

66506497 is an equidigital number, since it uses as much as digits as its factorization.

66506497 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 272160, while the sum is 43.

The square root of 66506497 is about 8155.1515620496. The cubic root of 66506497 is about 405.1551445439.

The spelling of 66506497 in words is "sixty-six million, five hundred six thousand, four hundred ninety-seven".