99998861 has 4 divisors (see below), whose sum is σ = 100030812. Its totient is φ = 99966912.

The previous prime is 99998851. The next prime is 99998869. The reversal of 99998861 is 16889999.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16889999 = 7 ⋅2412857.

It can be written as a sum of positive squares in 2 ways, for example, as 72760900 + 27237961 = 8530^2 + 5219^2 .

It is a cyclic number.

It is not a de Polignac number, because 99998861 - 2⁶ = 99998797 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a nialpdrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 99998861.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99998869) 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 3 ways as a sum of consecutive naturals, for example, 10700 + ... + 17733.

It is an arithmetic number, because the mean of its divisors is an integer number (25007703).

Almost surely, 2^99998861 is an apocalyptic number.

It is an amenable number.

99998861 is a deficient number, since it is larger than the sum of its proper divisors (31951).

99998861 is a wasteful number, since it uses less digits than its factorization.

99998861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31950.

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

The square root of 99998861 is about 9999.9430498378. The cubic root of 99998861 is about 464.1571210980.

The spelling of 99998861 in words is "ninety-nine million, nine hundred ninety-eight thousand, eight hundred sixty-one".