66135947 has 2 divisors, whose sum is σ = 66135948. Its totient is φ = 66135946.

The previous prime is 66135931. The next prime is 66135959. The reversal of 66135947 is 74953166.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66135947 - 2⁴ = 66135931 is a prime.

It is not a weakly prime, because it can be changed into another prime (66135907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33067973 + 33067974.

It is an arithmetic number, because the mean of its divisors is an integer number (33067974).

Almost surely, 2^66135947 is an apocalyptic number.

66135947 is a deficient number, since it is larger than the sum of its proper divisors (1).

66135947 is an equidigital number, since it uses as much as digits as its factorization.

66135947 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 136080, while the sum is 41.

The square root of 66135947 is about 8132.4010599576. The cubic root of 66135947 is about 404.4012837154.

The spelling of 66135947 in words is "sixty-six million, one hundred thirty-five thousand, nine hundred forty-seven".