66730561 has 8 divisors (see below), whose sum is σ = 67262400. Its totient is φ = 66201360.

The previous prime is 66730519. The next prime is 66730571. The reversal of 66730561 is 16503766.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66730561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66730571) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 96226 + ... + 96916.

It is an arithmetic number, because the mean of its divisors is an integer number (8407800).

Almost surely, 2^66730561 is an apocalyptic number.

It is an amenable number.

66730561 is a deficient number, since it is larger than the sum of its proper divisors (531839).

66730561 is a wasteful number, since it uses less digits than its factorization.

66730561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1319.

The product of its (nonzero) digits is 22680, while the sum is 34.

The square root of 66730561 is about 8168.8775850786. The cubic root of 66730561 is about 405.6096310900.

The spelling of 66730561 in words is "sixty-six million, seven hundred thirty thousand, five hundred sixty-one".