999824401 has 4 divisors (see below), whose sum is σ = 1024210404. Its totient is φ = 975438400.

The previous prime is 999824393. The next prime is 999824407. The reversal of 999824401 is 104428999.

It is a Cunningham number, because it is equal to 31620²+1.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 104428999 = 1049 ⋅99551.

It can be written as a sum of positive squares in 2 ways, for example, as 48163600 + 951660801 = 6940^2 + 30849^2 .

It is a cyclic number.

It is not a de Polignac number, because 999824401 - 2³ = 999824393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (999824407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12192940 + ... + 12193021.

It is an arithmetic number, because the mean of its divisors is an integer number (256052601).

Almost surely, 2^999824401 is an apocalyptic number.

It is an amenable number.

999824401 is a deficient number, since it is larger than the sum of its proper divisors (24386003).

999824401 is a wasteful number, since it uses less digits than its factorization.

999824401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24386002.

The product of its (nonzero) digits is 186624, while the sum is 46.

The square root of 999824401 is about 31620.0000158128. Note that the first 4 decimals coincide. The cubic root of 999824401 is about 999.9414635736.

The spelling of 999824401 in words is "nine hundred ninety-nine million, eight hundred twenty-four thousand, four hundred one".