66727321 has 2 divisors, whose sum is σ = 66727322. Its totient is φ = 66727320.

The previous prime is 66727303. The next prime is 66727327. The reversal of 66727321 is 12372766.

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., 48108096 + 18619225 = 6936^2 + 4315^2 .

It is a cyclic number.

It is not a de Polignac number, because 66727321 - 2¹¹ = 66725273 is a prime.

It is not a weakly prime, because it can be changed into another prime (66727327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33363660 + 33363661.

It is an arithmetic number, because the mean of its divisors is an integer number (33363661).

Almost surely, 2^66727321 is an apocalyptic number.

It is an amenable number.

66727321 is a deficient number, since it is larger than the sum of its proper divisors (1).

66727321 is an equidigital number, since it uses as much as digits as its factorization.

66727321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 21168, while the sum is 34.

The square root of 66727321 is about 8168.6792690128. The cubic root of 66727321 is about 405.6030663993.

The spelling of 66727321 in words is "sixty-six million, seven hundred twenty-seven thousand, three hundred twenty-one".