66906143 has 2 divisors, whose sum is σ = 66906144. Its totient is φ = 66906142.

The previous prime is 66906139. The next prime is 66906157. The reversal of 66906143 is 34160966.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66906143 - 2² = 66906139 is a prime.

It is a super-2 number, since 2×66906143² = 8952863942272898, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66906113) 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, 33453071 + 33453072.

It is an arithmetic number, because the mean of its divisors is an integer number (33453072).

Almost surely, 2^66906143 is an apocalyptic number.

66906143 is a deficient number, since it is larger than the sum of its proper divisors (1).

66906143 is an equidigital number, since it uses as much as digits as its factorization.

66906143 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 23328, while the sum is 35.

The square root of 66906143 is about 8179.6175338459. The cubic root of 66906143 is about 405.9650673270.

The spelling of 66906143 in words is "sixty-six million, nine hundred six thousand, one hundred forty-three".