991487671305 has 32 divisors (see below), whose sum is σ = 1642004732160. Its totient is φ = 510272421120.

The previous prime is 991487671301. The next prime is 991487671379. The reversal of 991487671305 is 503176784199.

It is not a de Polignac number, because 991487671305 - 2² = 991487671301 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (991487671301) 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 31 ways as a sum of consecutive naturals, for example, 136435 + ... + 1414775.

It is an arithmetic number, because the mean of its divisors is an integer number (51312647880).

Almost surely, 2^991487671305 is an apocalyptic number.

It is an amenable number.

991487671305 is a deficient number, since it is larger than the sum of its proper divisors (650517060855).

991487671305 is a wasteful number, since it uses less digits than its factorization.

991487671305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1280161.

The product of its (nonzero) digits is 11430720, while the sum is 60.

The spelling of 991487671305 in words is "nine hundred ninety-one billion, four hundred eighty-seven million, six hundred seventy-one thousand, three hundred five".