66909679 has 2 divisors, whose sum is σ = 66909680. Its totient is φ = 66909678.

The previous prime is 66909649. The next prime is 66909701. The reversal of 66909679 is 97690966.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66909679 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66909649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33454839 + 33454840.

It is an arithmetic number, because the mean of its divisors is an integer number (33454840).

Almost surely, 2^66909679 is an apocalyptic number.

66909679 is a deficient number, since it is larger than the sum of its proper divisors (1).

66909679 is an equidigital number, since it uses as much as digits as its factorization.

66909679 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1102248, while the sum is 52.

The square root of 66909679 is about 8179.8336780157. The cubic root of 66909679 is about 405.9722189732.

The spelling of 66909679 in words is "sixty-six million, nine hundred nine thousand, six hundred seventy-nine".