991487671365 has 16 divisors (see below), whose sum is σ = 1587066777216. Its totient is φ = 528564590400.

The previous prime is 991487671301. The next prime is 991487671379. The reversal of 991487671365 is 563176784199.

991487671365 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 991487671365 - 2⁶ = 991487671301 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 991487671296 and 991487671305.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14266326 + ... + 14335655.

It is an arithmetic number, because the mean of its divisors is an integer number (99191673576).

Almost surely, 2^991487671365 is an apocalyptic number.

It is an amenable number.

991487671365 is a deficient number, since it is larger than the sum of its proper divisors (595579105851).

991487671365 is a wasteful number, since it uses less digits than its factorization.

991487671365 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28604300.

The product of its digits is 68584320, while the sum is 66.

The spelling of 991487671365 in words is "nine hundred ninety-one billion, four hundred eighty-seven million, six hundred seventy-one thousand, three hundred sixty-five".