66188557291 has 2 divisors, whose sum is σ = 66188557292. Its totient is φ = 66188557290.

The previous prime is 66188557199. The next prime is 66188557307. The reversal of 66188557291 is 19275588166.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66188557291 - 2¹³ = 66188549099 is a prime.

It is not a weakly prime, because it can be changed into another prime (66188557991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33094278645 + 33094278646.

It is an arithmetic number, because the mean of its divisors is an integer number (33094278646).

Almost surely, 2^66188557291 is an apocalyptic number.

66188557291 is a deficient number, since it is larger than the sum of its proper divisors (1).

66188557291 is an equidigital number, since it uses as much as digits as its factorization.

66188557291 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7257600, while the sum is 58.

The spelling of 66188557291 in words is "sixty-six billion, one hundred eighty-eight million, five hundred fifty-seven thousand, two hundred ninety-one".