66539723 has 2 divisors, whose sum is σ = 66539724. Its totient is φ = 66539722.

The previous prime is 66539701. The next prime is 66539741. The reversal of 66539723 is 32793566.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66539723 - 2¹⁸ = 66277579 is a prime.

It is not a weakly prime, because it can be changed into another prime (66539773) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33269861 + 33269862.

It is an arithmetic number, because the mean of its divisors is an integer number (33269862).

Almost surely, 2^66539723 is an apocalyptic number.

66539723 is a deficient number, since it is larger than the sum of its proper divisors (1).

66539723 is an equidigital number, since it uses as much as digits as its factorization.

66539723 is an evil number, because the sum of its binary digits is even.

The product of its digits is 204120, while the sum is 41.

The square root of 66539723 is about 8157.1884249415. The cubic root of 66539723 is about 405.2226038362. Note that the first 3 decimals are identical.

The spelling of 66539723 in words is "sixty-six million, five hundred thirty-nine thousand, seven hundred twenty-three".