66019663 has 4 divisors (see below), whose sum is σ = 67555048. Its totient is φ = 64484280.

The previous prime is 66019651. The next prime is 66019669. The reversal of 66019663 is 36691066.

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 66019663 - 2¹³ = 66011471 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 (66019669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 767628 + ... + 767713.

It is an arithmetic number, because the mean of its divisors is an integer number (16888762).

Almost surely, 2^66019663 is an apocalyptic number.

66019663 is a deficient number, since it is larger than the sum of its proper divisors (1535385).

66019663 is a wasteful number, since it uses less digits than its factorization.

66019663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1535384.

The product of its (nonzero) digits is 34992, while the sum is 37.

The square root of 66019663 is about 8125.2484885079. The cubic root of 66019663 is about 404.1641308564.

The spelling of 66019663 in words is "sixty-six million, nineteen thousand, six hundred sixty-three".