66563504501 has 4 divisors (see below), whose sum is σ = 71683774092. Its totient is φ = 61443234912.

The previous prime is 66563504467. The next prime is 66563504503. The reversal of 66563504501 is 10540536566.

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

It can be written as a sum of positive squares in 2 ways, for example, as 4563002500 + 62000502001 = 67550^2 + 248999^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66563504501 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 (66563504503) 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, 2560134776 + ... + 2560134801.

It is an arithmetic number, because the mean of its divisors is an integer number (17920943523).

Almost surely, 2^66563504501 is an apocalyptic number.

It is an amenable number.

66563504501 is a deficient number, since it is larger than the sum of its proper divisors (5120269591).

66563504501 is a wasteful number, since it uses less digits than its factorization.

66563504501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5120269590.

The product of its (nonzero) digits is 324000, while the sum is 41.

The spelling of 66563504501 in words is "sixty-six billion, five hundred sixty-three million, five hundred four thousand, five hundred one".