66634943 has 2 divisors, whose sum is σ = 66634944. Its totient is φ = 66634942.

The previous prime is 66634937. The next prime is 66634949. The reversal of 66634943 is 34943666.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (66634937) and next prime (66634949).

It is a cyclic number.

It is not a de Polignac number, because 66634943 - 2⁴ = 66634927 is a prime.

It is a super-2 number, since 2×66634943² = 8880431257226498, which contains 22 as substring.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66634943.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66634949) 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, 33317471 + 33317472.

It is an arithmetic number, because the mean of its divisors is an integer number (33317472).

Almost surely, 2^66634943 is an apocalyptic number.

66634943 is a deficient number, since it is larger than the sum of its proper divisors (1).

66634943 is an equidigital number, since it uses as much as digits as its factorization.

66634943 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 279936, while the sum is 41.

The square root of 66634943 is about 8163.0229082124. The cubic root of 66634943 is about 405.4158062508.

The spelling of 66634943 in words is "sixty-six million, six hundred thirty-four thousand, nine hundred forty-three".