66985487 has 2 divisors, whose sum is σ = 66985488. Its totient is φ = 66985486.

The previous prime is 66985441. The next prime is 66985489. The reversal of 66985487 is 78458966.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66985487 - 2²⁴ = 50208271 is a prime.

Together with 66985489, it forms a pair of twin primes.

It is a Chen prime.

It is a zygodrome in base 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66985489) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33492743 + 33492744.

It is an arithmetic number, because the mean of its divisors is an integer number (33492744).

Almost surely, 2^66985487 is an apocalyptic number.

66985487 is a deficient number, since it is larger than the sum of its proper divisors (1).

66985487 is an equidigital number, since it uses as much as digits as its factorization.

66985487 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2903040, while the sum is 53.

The square root of 66985487 is about 8184.4662012864. The cubic root of 66985487 is about 406.1254819330.

The spelling of 66985487 in words is "sixty-six million, nine hundred eighty-five thousand, four hundred eighty-seven".