66677773 has 2 divisors, whose sum is σ = 66677774. Its totient is φ = 66677772.

The previous prime is 66677761. The next prime is 66677777. The reversal of 66677773 is 37777666.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 35964009 + 30713764 = 5997^2 + 5542^2 .

It is a cyclic number.

It is not a de Polignac number, because 66677773 - 2²⁵ = 33123341 is a prime.

It is a super-3 number, since 3×66677773³ (a number of 24 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66677777) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33338886 + 33338887.

It is an arithmetic number, because the mean of its divisors is an integer number (33338887).

Almost surely, 2^66677773 is an apocalyptic number.

It is an amenable number.

66677773 is a deficient number, since it is larger than the sum of its proper divisors (1).

66677773 is an equidigital number, since it uses as much as digits as its factorization.

66677773 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1555848, while the sum is 49.

The square root of 66677773 is about 8165.6459021929. The cubic root of 66677773 is about 405.5026487755.

The spelling of 66677773 in words is "sixty-six million, six hundred seventy-seven thousand, seven hundred seventy-three".