99891986 has 8 divisors (see below), whose sum is σ = 150144624. Its totient is φ = 49843780.

The previous prime is 99891947. The next prime is 99891989. The reversal of 99891986 is 68919899.

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

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (99891989) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49880 + ... + 51843.

It is an arithmetic number, because the mean of its divisors is an integer number (18768078).

Almost surely, 2^99891986 is an apocalyptic number.

99891986 is a deficient number, since it is larger than the sum of its proper divisors (50252638).

99891986 is a wasteful number, since it uses less digits than its factorization.

99891986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102216.

The product of its digits is 2519424, while the sum is 59.

The square root of 99891986 is about 9994.5978408338. The cubic root of 99891986 is about 463.9917042958.

Adding to 99891986 its sum of digits (59), we get a triangular number (99892045 = T₁₄₁₃₄).

The spelling of 99891986 in words is "ninety-nine million, eight hundred ninety-one thousand, nine hundred eighty-six".