66936817 has 2 divisors, whose sum is σ = 66936818. Its totient is φ = 66936816.

The previous prime is 66936809. The next prime is 66936833. The reversal of 66936817 is 71863966.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 41525136 + 25411681 = 6444^2 + 5041^2 .

It is a cyclic number.

It is not a de Polignac number, because 66936817 - 2³ = 66936809 is a prime.

It is not a weakly prime, because it can be changed into another prime (66936017) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33468408 + 33468409.

It is an arithmetic number, because the mean of its divisors is an integer number (33468409).

Almost surely, 2^66936817 is an apocalyptic number.

It is an amenable number.

66936817 is a deficient number, since it is larger than the sum of its proper divisors (1).

66936817 is an equidigital number, since it uses as much as digits as its factorization.

66936817 is an evil number, because the sum of its binary digits is even.

The product of its digits is 326592, while the sum is 46.

The square root of 66936817 is about 8181.4923455321. The cubic root of 66936817 is about 406.0270978540.

The spelling of 66936817 in words is "sixty-six million, nine hundred thirty-six thousand, eight hundred seventeen".