66921079 has 2 divisors, whose sum is σ = 66921080. Its totient is φ = 66921078.

The previous prime is 66921073. The next prime is 66921083. The reversal of 66921079 is 97012966.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66921079 - 2¹¹ = 66919031 is a 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 (66921073) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33460539 + 33460540.

It is an arithmetic number, because the mean of its divisors is an integer number (33460540).

Almost surely, 2^66921079 is an apocalyptic number.

66921079 is a deficient number, since it is larger than the sum of its proper divisors (1).

66921079 is an equidigital number, since it uses as much as digits as its factorization.

66921079 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40824, while the sum is 40.

The square root of 66921079 is about 8180.5304840212. The cubic root of 66921079 is about 405.9952740356.

The spelling of 66921079 in words is "sixty-six million, nine hundred twenty-one thousand, seventy-nine".