66312773 has 2 divisors, whose sum is σ = 66312774. Its totient is φ = 66312772.

The previous prime is 66312713. The next prime is 66312787. The reversal of 66312773 is 37721366.

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., 43864129 + 22448644 = 6623^2 + 4738^2 .

It is a cyclic number.

It is not a de Polignac number, because 66312773 - 2⁸ = 66312517 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66312713) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33156386 + 33156387.

It is an arithmetic number, because the mean of its divisors is an integer number (33156387).

Almost surely, 2^66312773 is an apocalyptic number.

It is an amenable number.

66312773 is a deficient number, since it is larger than the sum of its proper divisors (1).

66312773 is an equidigital number, since it uses as much as digits as its factorization.

66312773 is an evil number, because the sum of its binary digits is even.

The product of its digits is 31752, while the sum is 35.

The square root of 66312773 is about 8143.2654997857. The cubic root of 66312773 is about 404.7613754600.

The spelling of 66312773 in words is "sixty-six million, three hundred twelve thousand, seven hundred seventy-three".