999112409 has 4 divisors (see below), whose sum is σ = 1001252304. Its totient is φ = 996972516.

The previous prime is 999112363. The next prime is 999112451. The reversal of 999112409 is 904211999.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 904211999 = 31 ⋅29168129.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-999112409 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 999112409.

It is not an unprimeable number, because it can be changed into a prime (999112469) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1069247 + ... + 1070180.

It is an arithmetic number, because the mean of its divisors is an integer number (250313076).

Almost surely, 2^999112409 is an apocalyptic number.

It is an amenable number.

999112409 is a deficient number, since it is larger than the sum of its proper divisors (2139895).

999112409 is a wasteful number, since it uses less digits than its factorization.

999112409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2139894.

The product of its (nonzero) digits is 52488, while the sum is 44.

The square root of 999112409 is about 31608.7394402244. The cubic root of 999112409 is about 999.7040487548.

The spelling of 999112409 in words is "nine hundred ninety-nine million, one hundred twelve thousand, four hundred nine".