66505763 has 4 divisors (see below), whose sum is σ = 66527208. Its totient is φ = 66484320.

The previous prime is 66505753. The next prime is 66505841. The reversal of 66505763 is 36750566.

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 66505763 - 2²⁰ = 65457187 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66505753) 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, 5081 + ... + 12602.

It is an arithmetic number, because the mean of its divisors is an integer number (16631802).

Almost surely, 2^66505763 is an apocalyptic number.

66505763 is a deficient number, since it is larger than the sum of its proper divisors (21445).

66505763 is a wasteful number, since it uses less digits than its factorization.

66505763 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21444.

The product of its (nonzero) digits is 113400, while the sum is 38.

The square root of 66505763 is about 8155.1065596962. The cubic root of 66505763 is about 405.1536540380.

The spelling of 66505763 in words is "sixty-six million, five hundred five thousand, seven hundred sixty-three".