66985129 has 2 divisors, whose sum is σ = 66985130. Its totient is φ = 66985128.

The previous prime is 66985109. The next prime is 66985159. The reversal of 66985129 is 92158966.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 36481600 + 30503529 = 6040^2 + 5523^2 .

It is a cyclic number.

It is not a de Polignac number, because 66985129 - 2¹³ = 66976937 is a prime.

It is not a weakly prime, because it can be changed into another prime (66985109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33492564 + 33492565.

It is an arithmetic number, because the mean of its divisors is an integer number (33492565).

Almost surely, 2^66985129 is an apocalyptic number.

It is an amenable number.

66985129 is a deficient number, since it is larger than the sum of its proper divisors (1).

66985129 is an equidigital number, since it uses as much as digits as its factorization.

66985129 is an evil number, because the sum of its binary digits is even.

The product of its digits is 233280, while the sum is 46.

The square root of 66985129 is about 8184.4443305578. Note that the first 3 decimals coincide. The cubic root of 66985129 is about 406.1247584272.

The spelling of 66985129 in words is "sixty-six million, nine hundred eighty-five thousand, one hundred twenty-nine".