66205723 has 2 divisors, whose sum is σ = 66205724. Its totient is φ = 66205722.

The previous prime is 66205721. The next prime is 66205781. The reversal of 66205723 is 32750266.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66205723 - 2¹ = 66205721 is a prime.

Together with 66205721, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (66205721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33102861 + 33102862.

It is an arithmetic number, because the mean of its divisors is an integer number (33102862).

Almost surely, 2^66205723 is an apocalyptic number.

66205723 is a deficient number, since it is larger than the sum of its proper divisors (1).

66205723 is an equidigital number, since it uses as much as digits as its factorization.

66205723 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15120, while the sum is 31.

The square root of 66205723 is about 8136.6899289576. The cubic root of 66205723 is about 404.5434534307.

Adding to 66205723 its reverse (32750266), we get a palindrome (98955989).

The spelling of 66205723 in words is "sixty-six million, two hundred five thousand, seven hundred twenty-three".