66643023 has 4 divisors (see below), whose sum is σ = 88857368. Its totient is φ = 44428680.

The previous prime is 66642967. The next prime is 66643061. The reversal of 66643023 is 32034666.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 66643023 - 2¹⁰ = 66641999 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 (66643523) 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, 11107168 + ... + 11107173.

It is an arithmetic number, because the mean of its divisors is an integer number (22214342).

Almost surely, 2^66643023 is an apocalyptic number.

66643023 is a deficient number, since it is larger than the sum of its proper divisors (22214345).

66643023 is a wasteful number, since it uses less digits than its factorization.

66643023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22214344.

The product of its (nonzero) digits is 15552, while the sum is 30.

The square root of 66643023 is about 8163.5178079061. The cubic root of 66643023 is about 405.4321921848.

Adding to 66643023 its reverse (32034666), we get a palindrome (98677689).

The spelling of 66643023 in words is "sixty-six million, six hundred forty-three thousand, twenty-three".