106666991 has 2 divisors, whose sum is σ = 106666992. Its totient is φ = 106666990.

The previous prime is 106666981. The next prime is 106667039. The reversal of 106666991 is 199666601.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 106666991 - 2⁶ = 106666927 is a prime.

It is a super-2 number, since 2×106666991² = 22755693937988162, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (106666951) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 53333495 + 53333496.

It is an arithmetic number, because the mean of its divisors is an integer number (53333496).

Almost surely, 2^106666991 is an apocalyptic number.

106666991 is a deficient number, since it is larger than the sum of its proper divisors (1).

106666991 is an equidigital number, since it uses as much as digits as its factorization.

106666991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 104976, while the sum is 44.

The square root of 106666991 is about 10327.9712915945. The cubic root of 106666991 is about 474.2529212728.

The spelling of 106666991 in words is "one hundred six million, six hundred sixty-six thousand, nine hundred ninety-one".