66078947 has 12 divisors (see below), whose sum is σ = 73364928. Its totient is φ = 59466000.

The previous prime is 66078911. The next prime is 66078953. The reversal of 66078947 is 74987066.

It is a happy number.

66078947 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 66078947 - 2¹⁰ = 66077923 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66078247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9518 + ... + 14924.

It is an arithmetic number, because the mean of its divisors is an integer number (6113744).

Almost surely, 2^66078947 is an apocalyptic number.

66078947 is a deficient number, since it is larger than the sum of its proper divisors (7285981).

66078947 is a wasteful number, since it uses less digits than its factorization.

66078947 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5530 (or 5519 counting only the distinct ones).

The product of its (nonzero) digits is 508032, while the sum is 47.

The square root of 66078947 is about 8128.8958044743. The cubic root of 66078947 is about 404.2850710776.

The spelling of 66078947 in words is "sixty-six million, seventy-eight thousand, nine hundred forty-seven".