66693810427 has 2 divisors, whose sum is σ = 66693810428. Its totient is φ = 66693810426.

The previous prime is 66693810377. The next prime is 66693810433. The reversal of 66693810427 is 72401839666.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66693810427 - 2¹⁵ = 66693777659 is a prime.

It is a super-2 number, since 2×66693810427² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (66693810497) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33346905213 + 33346905214.

It is an arithmetic number, because the mean of its divisors is an integer number (33346905214).

Almost surely, 2^66693810427 is an apocalyptic number.

66693810427 is a deficient number, since it is larger than the sum of its proper divisors (1).

66693810427 is an equidigital number, since it uses as much as digits as its factorization.

66693810427 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2612736, while the sum is 52.

The spelling of 66693810427 in words is "sixty-six billion, six hundred ninety-three million, eight hundred ten thousand, four hundred twenty-seven".