66723823 has 4 divisors (see below), whose sum is σ = 66811360. Its totient is φ = 66636288.

The previous prime is 66723821. The next prime is 66723829. The reversal of 66723823 is 32832766.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32832766 = 2 ⋅16416383.

It is a cyclic number.

It is not a de Polignac number, because 66723823 - 2¹ = 66723821 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66723821) 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, 42615 + ... + 44152.

It is an arithmetic number, because the mean of its divisors is an integer number (16702840).

Almost surely, 2^66723823 is an apocalyptic number.

66723823 is a deficient number, since it is larger than the sum of its proper divisors (87537).

66723823 is an equidigital number, since it uses as much as digits as its factorization.

66723823 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87536.

The product of its digits is 72576, while the sum is 37.

The square root of 66723823 is about 8168.4651557070. The cubic root of 66723823 is about 405.5959787262.

The spelling of 66723823 in words is "sixty-six million, seven hundred twenty-three thousand, eight hundred twenty-three".