66681107 has 2 divisors, whose sum is σ = 66681108. Its totient is φ = 66681106.

The previous prime is 66681091. The next prime is 66681133. The reversal of 66681107 is 70118666.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66681107 - 2⁴ = 66681091 is a prime.

It is not a weakly prime, because it can be changed into another prime (66681007) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33340553 + 33340554.

It is an arithmetic number, because the mean of its divisors is an integer number (33340554).

Almost surely, 2^66681107 is an apocalyptic number.

66681107 is a deficient number, since it is larger than the sum of its proper divisors (1).

66681107 is an equidigital number, since it uses as much as digits as its factorization.

66681107 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12096, while the sum is 35.

The square root of 66681107 is about 8165.8500476068. The cubic root of 66681107 is about 405.5094072661.

The spelling of 66681107 in words is "sixty-six million, six hundred eighty-one thousand, one hundred seven".