66123907 has 2 divisors, whose sum is σ = 66123908. Its totient is φ = 66123906.

The previous prime is 66123901. The next prime is 66123917. The reversal of 66123907 is 70932166.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66123907 - 2⁷ = 66123779 is a prime.

It is not a weakly prime, because it can be changed into another prime (66123901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33061953 + 33061954.

It is an arithmetic number, because the mean of its divisors is an integer number (33061954).

Almost surely, 2^66123907 is an apocalyptic number.

66123907 is a deficient number, since it is larger than the sum of its proper divisors (1).

66123907 is an equidigital number, since it uses as much as digits as its factorization.

66123907 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13608, while the sum is 34.

The square root of 66123907 is about 8131.6607774796. The cubic root of 66123907 is about 404.3767419084.

The spelling of 66123907 in words is "sixty-six million, one hundred twenty-three thousand, nine hundred seven".