66662777 has 2 divisors, whose sum is σ = 66662778. Its totient is φ = 66662776.

The previous prime is 66662753. The next prime is 66662801. The reversal of 66662777 is 77726666.

It is a balanced prime because it is at equal distance from previous prime (66662753) and next prime (66662801).

It can be written as a sum of positive squares in only one way, i.e., 66650896 + 11881 = 8164^2 + 109^2 .

It is a cyclic number.

It is not a de Polignac number, because 66662777 - 2¹⁶ = 66597241 is a prime.

It is a super-3 number, since 3×66662777³ (a number of 24 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (66662977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33331388 + 33331389.

It is an arithmetic number, because the mean of its divisors is an integer number (33331389).

Almost surely, 2^66662777 is an apocalyptic number.

It is an amenable number.

66662777 is a deficient number, since it is larger than the sum of its proper divisors (1).

66662777 is an equidigital number, since it uses as much as digits as its factorization.

66662777 is an evil number, because the sum of its binary digits is even.

The product of its digits is 889056, while the sum is 47.

The square root of 66662777 is about 8164.7276133378. The cubic root of 66662777 is about 405.4722469721.

The spelling of 66662777 in words is "sixty-six million, six hundred sixty-two thousand, seven hundred seventy-seven".