91989589287 has 32 divisors (see below), whose sum is σ = 134948782080. Its totient is φ = 55478545920.

The previous prime is 91989589259. The next prime is 91989589297. The reversal of 91989589287 is 78298598919.

It is not a de Polignac number, because 91989589287 - 2⁸ = 91989589031 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91989589217) 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, 190362 + ... + 469272.

It is an arithmetic number, because the mean of its divisors is an integer number (4217149440).

Almost surely, 2^91989589287 is an apocalyptic number.

91989589287 is a deficient number, since it is larger than the sum of its proper divisors (42959192793).

91989589287 is a wasteful number, since it uses less digits than its factorization.

91989589287 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 279183.

The product of its digits is 235146240, while the sum is 75.

The spelling of 91989589287 in words is "ninety-one billion, nine hundred eighty-nine million, five hundred eighty-nine thousand, two hundred eighty-seven".