15899799 has 4 divisors (see below), whose sum is σ = 21199736. Its totient is φ = 10599864.

The previous prime is 15899797. The next prime is 15899839. The reversal of 15899799 is 99799851.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99799851 = 3 ⋅33266617.

It is not a de Polignac number, because 15899799 - 2¹ = 15899797 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 (15899791) 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, 2649964 + ... + 2649969.

It is an arithmetic number, because the mean of its divisors is an integer number (5299934).

Almost surely, 2^15899799 is an apocalyptic number.

15899799 is a deficient number, since it is larger than the sum of its proper divisors (5299937).

15899799 is an equidigital number, since it uses as much as digits as its factorization.

15899799 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5299936.

The product of its digits is 1837080, while the sum is 57.

The square root of 15899799 is about 3987.4552035101. The cubic root of 15899799 is about 251.4570857720.

The spelling of 15899799 in words is "fifteen million, eight hundred ninety-nine thousand, seven hundred ninety-nine".