66791 has 2 divisors, whose sum is σ = 66792. Its totient is φ = 66790.

The previous prime is 66763. The next prime is 66797. The reversal of 66791 is 19766.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66791 is a prime.

It is a super-2 number, since 2×66791² = 8922075362, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66797) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33395 + 33396.

It is an arithmetic number, because the mean of its divisors is an integer number (33396).

2⁶⁶⁷⁹¹ is an apocalyptic number.

66791 is a deficient number, since it is larger than the sum of its proper divisors (1).

66791 is an equidigital number, since it uses as much as digits as its factorization.

66791 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2268, while the sum is 29.

The square root of 66791 is about 258.4395480572. The cubic root of 66791 is about 40.5732049977.

The spelling of 66791 in words is "sixty-six thousand, seven hundred ninety-one".