99999851 has 4 divisors (see below), whose sum is σ = 114285552. Its totient is φ = 85714152.

The previous prime is 99999847. The next prime is 99999931. The reversal of 99999851 is 15899999.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 99999851 - 2² = 99999847 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (99999821) 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, 7142840 + ... + 7142853.

It is an arithmetic number, because the mean of its divisors is an integer number (28571388).

Almost surely, 2^99999851 is an apocalyptic number.

99999851 is a deficient number, since it is larger than the sum of its proper divisors (14285701).

99999851 is a wasteful number, since it uses less digits than its factorization.

99999851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14285700.

The product of its digits is 2361960, while the sum is 59.

The square root of 99999851 is about 9999.9925499972. The cubic root of 99999851 is about 464.1586528289.

The spelling of 99999851 in words is "ninety-nine million, nine hundred ninety-nine thousand, eight hundred fifty-one".