91891946385 has 48 divisors (see below), whose sum is σ = 168427703808. Its totient is φ = 46271289600.

The previous prime is 91891946371. The next prime is 91891946401. The reversal of 91891946385 is 58364919819.

91891946385 is a `hidden beast` number, since 9 + 1 + 8 + 91 + 9 + 463 + 85 = 666.

It is not a de Polignac number, because 91891946385 - 2⁷ = 91891946257 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 746127 + ... + 860516.

It is an arithmetic number, because the mean of its divisors is an integer number (3508910496).

Almost surely, 2^91891946385 is an apocalyptic number.

It is an amenable number.

91891946385 is a deficient number, since it is larger than the sum of its proper divisors (76535757423).

91891946385 is a wasteful number, since it uses less digits than its factorization.

91891946385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1606726 (or 1606723 counting only the distinct ones).

The product of its digits is 16796160, while the sum is 63.

The spelling of 91891946385 in words is "ninety-one billion, eight hundred ninety-one million, nine hundred forty-six thousand, three hundred eighty-five".