66571763653 has 4 divisors (see below), whose sum is σ = 68867341740. Its totient is φ = 64276185568.

The previous prime is 66571763647. The next prime is 66571763663. The reversal of 66571763653 is 35636717566.

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 32147414209 + 34424349444 = 179297^2 + 185538^2 .

It is not a de Polignac number, because 66571763653 - 2²⁹ = 66034892741 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66571763594 and 66571763603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66571763633) 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, 1147789000 + ... + 1147789057.

It is an arithmetic number, because the mean of its divisors is an integer number (17216835435).

Almost surely, 2^66571763653 is an apocalyptic number.

It is an amenable number.

66571763653 is a deficient number, since it is larger than the sum of its proper divisors (2295578087).

66571763653 is a wasteful number, since it uses less digits than its factorization.

66571763653 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2295578086.

The product of its digits is 14288400, while the sum is 55.

The spelling of 66571763653 in words is "sixty-six billion, five hundred seventy-one million, seven hundred sixty-three thousand, six hundred fifty-three".