66571996087 has 2 divisors, whose sum is σ = 66571996088. Its totient is φ = 66571996086.

The previous prime is 66571996081. The next prime is 66571996091. The reversal of 66571996087 is 78069917566.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66571996087 - 2¹¹ = 66571994039 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66571996081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33285998043 + 33285998044.

It is an arithmetic number, because the mean of its divisors is an integer number (33285998044).

Almost surely, 2^66571996087 is an apocalyptic number.

66571996087 is a deficient number, since it is larger than the sum of its proper divisors (1).

66571996087 is an equidigital number, since it uses as much as digits as its factorization.

66571996087 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 34292160, while the sum is 64.

The spelling of 66571996087 in words is "sixty-six billion, five hundred seventy-one million, nine hundred ninety-six thousand, eighty-seven".