66642077 has 2 divisors, whose sum is σ = 66642078. Its totient is φ = 66642076.

The previous prime is 66642071. The next prime is 66642083. The reversal of 66642077 is 77024666.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (66642071) and next prime (66642083).

It can be written as a sum of positive squares in only one way, i.e., 56235001 + 10407076 = 7499^2 + 3226^2 .

It is a cyclic number.

It is not a de Polignac number, because 66642077 - 2¹⁰ = 66641053 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66642077.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66642071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33321038 + 33321039.

It is an arithmetic number, because the mean of its divisors is an integer number (33321039).

Almost surely, 2^66642077 is an apocalyptic number.

It is an amenable number.

66642077 is a deficient number, since it is larger than the sum of its proper divisors (1).

66642077 is an equidigital number, since it uses as much as digits as its factorization.

66642077 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 84672, while the sum is 38.

The square root of 66642077 is about 8163.4598669927. The cubic root of 66642077 is about 405.4302738011.

The spelling of 66642077 in words is "sixty-six million, six hundred forty-two thousand, seventy-seven".