56660321 has 2 divisors, whose sum is σ = 56660322. Its totient is φ = 56660320.

The previous prime is 56660309. The next prime is 56660327. The reversal of 56660321 is 12306665.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 45697600 + 10962721 = 6760^2 + 3311^2 .

It is a cyclic number.

It is not a de Polignac number, because 56660321 - 2⁶ = 56660257 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (56660327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28330160 + 28330161.

It is an arithmetic number, because the mean of its divisors is an integer number (28330161).

Almost surely, 2^56660321 is an apocalyptic number.

It is an amenable number.

56660321 is a deficient number, since it is larger than the sum of its proper divisors (1).

56660321 is an equidigital number, since it uses as much as digits as its factorization.

56660321 is an evil number, because the sum of its binary digits is even.

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

The square root of 56660321 is about 7527.3050290260. The cubic root of 56660321 is about 384.0841128857.

Adding to 56660321 its reverse (12306665), we get a palindrome (68966986).

The spelling of 56660321 in words is "fifty-six million, six hundred sixty thousand, three hundred twenty-one".