66381503 has 4 divisors (see below), whose sum is σ = 66904320. Its totient is φ = 65858688.

The previous prime is 66381479. The next prime is 66381517. The reversal of 66381503 is 30518366.

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

It is a cyclic number.

It is not a de Polignac number, because 66381503 - 2⁶ = 66381439 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66381503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66381593) 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 3 ways as a sum of consecutive naturals, for example, 261218 + ... + 261471.

It is an arithmetic number, because the mean of its divisors is an integer number (16726080).

Almost surely, 2^66381503 is an apocalyptic number.

66381503 is a deficient number, since it is larger than the sum of its proper divisors (522817).

66381503 is a wasteful number, since it uses less digits than its factorization.

66381503 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 522816.

The product of its (nonzero) digits is 12960, while the sum is 32.

The square root of 66381503 is about 8147.4844584080. The cubic root of 66381503 is about 404.9011657422.

Adding to 66381503 its reverse (30518366), we get a palindrome (96899869).

The spelling of 66381503 in words is "sixty-six million, three hundred eighty-one thousand, five hundred three".