66503423 has 16 divisors (see below), whose sum is σ = 77168640. Its totient is φ = 56137536.

The previous prime is 66503417. The next prime is 66503429. The reversal of 66503423 is 32430566.

It is an interprime number because it is at equal distance from previous prime (66503417) and next prime (66503429).

It is not a de Polignac number, because 66503423 - 2¹⁰ = 66502399 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 (66503429) 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 15 ways as a sum of consecutive naturals, for example, 212315 + ... + 212627.

It is an arithmetic number, because the mean of its divisors is an integer number (4823040).

Almost surely, 2^66503423 is an apocalyptic number.

66503423 is a deficient number, since it is larger than the sum of its proper divisors (10665217).

66503423 is a wasteful number, since it uses less digits than its factorization.

66503423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 686.

The product of its (nonzero) digits is 12960, while the sum is 29.

The square root of 66503423 is about 8154.9630900452. The cubic root of 66503423 is about 405.1489022159.

Adding to 66503423 its reverse (32430566), we get a palindrome (98933989).

The spelling of 66503423 in words is "sixty-six million, five hundred three thousand, four hundred twenty-three".