106666591 has 2 divisors, whose sum is σ = 106666592. Its totient is φ = 106666590.

The previous prime is 106666583. The next prime is 106666607. The reversal of 106666591 is 195666601.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 106666591 - 2³ = 106666583 is a prime.

It is a super-2 number, since 2×106666591² = 22755523271122562, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (106666501) 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, 53333295 + 53333296.

It is an arithmetic number, because the mean of its divisors is an integer number (53333296).

Almost surely, 2^106666591 is an apocalyptic number.

106666591 is a deficient number, since it is larger than the sum of its proper divisors (1).

106666591 is an equidigital number, since it uses as much as digits as its factorization.

106666591 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 58320, while the sum is 40.

The square root of 106666591 is about 10327.9519266890. The cubic root of 106666591 is about 474.2523284577.

It can be divided in two parts, 106666 and 591, that multiplied together give a triangular number (63039606 = T₁₁₂₂₈).

The spelling of 106666591 in words is "one hundred six million, six hundred sixty-six thousand, five hundred ninety-one".