66666937 has 2 divisors, whose sum is σ = 66666938. Its totient is φ = 66666936.

The previous prime is 66666931. The next prime is 66666973. The reversal of 66666937 is 73966666.

It is a happy number.

Together with next prime (66666973) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 35093776 + 31573161 = 5924^2 + 5619^2 .

It is a cyclic number.

It is not a de Polignac number, because 66666937 - 2¹¹ = 66664889 is a prime.

It is not a weakly prime, because it can be changed into another prime (66666931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33333468 + 33333469.

It is an arithmetic number, because the mean of its divisors is an integer number (33333469).

Almost surely, 2^66666937 is an apocalyptic number.

It is an amenable number.

66666937 is a deficient number, since it is larger than the sum of its proper divisors (1).

66666937 is an equidigital number, since it uses as much as digits as its factorization.

66666937 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1469664, while the sum is 49.

The square root of 66666937 is about 8164.9823637287. The cubic root of 66666937 is about 405.4806811115.

The spelling of 66666937 in words is "sixty-six million, six hundred sixty-six thousand, nine hundred thirty-seven".