99999799 has 4 divisors (see below), whose sum is σ = 100050336. Its totient is φ = 99949264.

The previous prime is 99999787. The next prime is 99999821. The reversal of 99999799 is 99799999.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99799999 = 13 ⋅7676923.

It is a cyclic number.

It is not a de Polignac number, because 99999799 - 2²¹ = 97902647 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 (99990799) 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, 22174 + ... + 26299.

It is an arithmetic number, because the mean of its divisors is an integer number (25012584).

Almost surely, 2^99999799 is an apocalyptic number.

99999799 is a deficient number, since it is larger than the sum of its proper divisors (50537).

99999799 is a wasteful number, since it uses less digits than its factorization.

99999799 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50536.

The product of its digits is 33480783, while the sum is 70.

The square root of 99999799 is about 9999.9899499949. The cubic root of 99999799 is about 464.1585723746.

The spelling of 99999799 in words is "ninety-nine million, nine hundred ninety-nine thousand, seven hundred ninety-nine".