391066109 has 12 divisors (see below), whose sum is σ = 455514588. Its totient is φ = 334756800.

The previous prime is 391066103. The next prime is 391066127. The reversal of 391066109 is 901660193.

It can be written as a sum of positive squares in 2 ways, for example, as 46963609 + 344102500 = 6853^2 + 18550^2 .

It is not a de Polignac number, because 391066109 - 2²⁸ = 122630653 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (391066103) 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 in 11 ways as a sum of consecutive naturals, for example, 35369 + ... + 45089.

It is an arithmetic number, because the mean of its divisors is an integer number (37959549).

Almost surely, 2^391066109 is an apocalyptic number.

It is an amenable number.

391066109 is a deficient number, since it is larger than the sum of its proper divisors (64448479).

391066109 is an equidigital number, since it uses as much as digits as its factorization.

391066109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10556 (or 10549 counting only the distinct ones).

The product of its (nonzero) digits is 8748, while the sum is 35.

The square root of 391066109 is about 19775.3915005494. The cubic root of 391066109 is about 731.2794906265.

The spelling of 391066109 in words is "three hundred ninety-one million, sixty-six thousand, one hundred nine".