66945047 has 4 divisors (see below), whose sum is σ = 72094680. Its totient is φ = 61795416.

The previous prime is 66945013. The next prime is 66945049. The reversal of 66945047 is 74054966.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66945047 - 2⁸ = 66944791 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66944995 and 66945013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66945049) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2574797 + ... + 2574822.

It is an arithmetic number, because the mean of its divisors is an integer number (18023670).

Almost surely, 2^66945047 is an apocalyptic number.

66945047 is a deficient number, since it is larger than the sum of its proper divisors (5149633).

66945047 is a wasteful number, since it uses less digits than its factorization.

66945047 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5149632.

The product of its (nonzero) digits is 181440, while the sum is 41.

The square root of 66945047 is about 8181.9952945477. The cubic root of 66945047 is about 406.0437377553.

The spelling of 66945047 in words is "sixty-six million, nine hundred forty-five thousand, forty-seven".