66385649 has 8 divisors (see below), whose sum is σ = 72518592. Its totient is φ = 60269040.

The previous prime is 66385643. The next prime is 66385681. The reversal of 66385649 is 94658366.

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

It is a cyclic number.

It is not a de Polignac number, because 66385649 - 2⁴ = 66385633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66385643) 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, 5387 + ... + 12719.

It is an arithmetic number, because the mean of its divisors is an integer number (9064824).

Almost surely, 2^66385649 is an apocalyptic number.

It is an amenable number.

66385649 is a deficient number, since it is larger than the sum of its proper divisors (6132943).

66385649 is a wasteful number, since it uses less digits than its factorization.

66385649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8167.

The product of its digits is 933120, while the sum is 47.

The square root of 66385649 is about 8147.7388887961. The cubic root of 66385649 is about 404.9095952254.

The spelling of 66385649 in words is "sixty-six million, three hundred eighty-five thousand, six hundred forty-nine".