66704321 has 4 divisors (see below), whose sum is σ = 69004500. Its totient is φ = 64404144.

The previous prime is 66704317. The next prime is 66704333. The reversal of 66704321 is 12340766.

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

It can be written as a sum of positive squares in 2 ways, for example, as 32364721 + 34339600 = 5689^2 + 5860^2 .

It is a cyclic number.

It is not a de Polignac number, because 66704321 - 2² = 66704317 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29), and also a Moran number because the ratio is a prime number: 2300149 = 66704321 / (6 + 6 + 7 + 0 + 4 + 3 + 2 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66704371) 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, 1150046 + ... + 1150103.

It is an arithmetic number, because the mean of its divisors is an integer number (17251125).

Almost surely, 2^66704321 is an apocalyptic number.

It is an amenable number.

66704321 is a deficient number, since it is larger than the sum of its proper divisors (2300179).

66704321 is a wasteful number, since it uses less digits than its factorization.

66704321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2300178.

The product of its (nonzero) digits is 6048, while the sum is 29.

The square root of 66704321 is about 8167.2713313566. The cubic root of 66704321 is about 405.5564590904.

The spelling of 66704321 in words is "sixty-six million, seven hundred four thousand, three hundred twenty-one".