66056321 has 4 divisors (see below), whose sum is σ = 66737412. Its totient is φ = 65375232.

The previous prime is 66056317. The next prime is 66056377. The reversal of 66056321 is 12365066.

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 11296321 + 54760000 = 3361^2 + 7400^2 .

It is a cyclic number.

It is not a de Polignac number, because 66056321 - 2² = 66056317 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66052321) 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, 340400 + ... + 340593.

It is an arithmetic number, because the mean of its divisors is an integer number (16684353).

Almost surely, 2^66056321 is an apocalyptic number.

It is an amenable number.

66056321 is a deficient number, since it is larger than the sum of its proper divisors (681091).

66056321 is an equidigital number, since it uses as much as digits as its factorization.

66056321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 681090.

The product of its (nonzero) digits is 6480, while the sum is 29.

The square root of 66056321 is about 8127.5039833888. The cubic root of 66056321 is about 404.2389222477.

The spelling of 66056321 in words is "sixty-six million, fifty-six thousand, three hundred twenty-one".