66665423 has 8 divisors (see below), whose sum is σ = 72845136. Its totient is φ = 60505600.

The previous prime is 66665419. The next prime is 66665429. The reversal of 66665423 is 32456666.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66665423 - 2² = 66665419 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 (66665429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2543 + ... + 11823.

It is an arithmetic number, because the mean of its divisors is an integer number (9105642).

Almost surely, 2^66665423 is an apocalyptic number.

66665423 is a deficient number, since it is larger than the sum of its proper divisors (6179713).

66665423 is a wasteful number, since it uses less digits than its factorization.

66665423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9945.

The product of its digits is 155520, while the sum is 38.

The square root of 66665423 is about 8164.8896502035. The cubic root of 66665423 is about 405.4776116119.

The spelling of 66665423 in words is "sixty-six million, six hundred sixty-five thousand, four hundred twenty-three".