99891687 has 8 divisors (see below), whose sum is σ = 152215936. Its totient is φ = 57080952.

The previous prime is 99891679. The next prime is 99891733. The reversal of 99891687 is 78619899.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 99891687 - 2³ = 99891679 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99891637) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 2378353 + ... + 2378394.

It is an arithmetic number, because the mean of its divisors is an integer number (19026992).

Almost surely, 2^99891687 is an apocalyptic number.

99891687 is a deficient number, since it is larger than the sum of its proper divisors (52324249).

99891687 is a wasteful number, since it uses less digits than its factorization.

99891687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4756757.

The product of its digits is 1959552, while the sum is 57.

The square root of 99891687 is about 9994.5828827420. The cubic root of 99891687 is about 463.9912413502.

The spelling of 99891687 in words is "ninety-nine million, eight hundred ninety-one thousand, six hundred eighty-seven".