66571156117 has 2 divisors, whose sum is σ = 66571156118. Its totient is φ = 66571156116.

The previous prime is 66571156109. The next prime is 66571156133. The reversal of 66571156117 is 71165117566.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 44824934961 + 21746221156 = 211719^2 + 147466^2 .

It is a cyclic number.

It is not a de Polignac number, because 66571156117 - 2³ = 66571156109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66571157117) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33285578058 + 33285578059.

It is an arithmetic number, because the mean of its divisors is an integer number (33285578059).

Almost surely, 2^66571156117 is an apocalyptic number.

It is an amenable number.

66571156117 is a deficient number, since it is larger than the sum of its proper divisors (1).

66571156117 is an equidigital number, since it uses as much as digits as its factorization.

66571156117 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 264600, while the sum is 46.

The spelling of 66571156117 in words is "sixty-six billion, five hundred seventy-one million, one hundred fifty-six thousand, one hundred seventeen".