91685001668 has 12 divisors (see below), whose sum is σ = 172790964780. Its totient is φ = 42316154592.

The previous prime is 91685001587. The next prime is 91685001677. The reversal of 91685001668 is 86610058619.

It can be written as a sum of positive squares in 2 ways, for example, as 53787814084 + 37897187584 = 231922^2 + 194672^2 .

It is a super-2 number, since 2×91685001668² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

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 in 3 ways as a sum of consecutive naturals, for example, 881586503 + ... + 881586606.

It is an arithmetic number, because the mean of its divisors is an integer number (14399247065).

Almost surely, 2^91685001668 is an apocalyptic number.

It is an amenable number.

91685001668 is a deficient number, since it is larger than the sum of its proper divisors (81105963112).

91685001668 is a wasteful number, since it uses less digits than its factorization.

91685001668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1763173126 (or 1763173124 counting only the distinct ones).

The product of its (nonzero) digits is 622080, while the sum is 50.

The spelling of 91685001668 in words is "ninety-one billion, six hundred eighty-five million, one thousand, six hundred sixty-eight".