999999801 has 6 divisors (see below), whose sum is σ = 1444444170. Its totient is φ = 666666528.

The previous prime is 999999797. The next prime is 999999883. The reversal of 999999801 is 108999999.

It can be written as a sum of positive squares in only one way, i.e., 825125625 + 174874176 = 28725^2 + 13224^2 .

It is not a de Polignac number, because 999999801 - 2² = 999999797 is a prime.

It is not an unprimeable number, because it can be changed into a prime (999999001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 55555536 + ... + 55555553.

It is an arithmetic number, because the mean of its divisors is an integer number (240740695).

Almost surely, 2^999999801 is an apocalyptic number.

It is an amenable number.

999999801 is a deficient number, since it is larger than the sum of its proper divisors (444444369).

999999801 is a wasteful number, since it uses less digits than its factorization.

999999801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111111095 (or 111111092 counting only the distinct ones).

The product of its (nonzero) digits is 4251528, while the sum is 63.

The square root of 999999801 is about 31622.7734552174. The cubic root of 999999801 is about 999.9999336667. Note that the first 4 decimals are identical.

The spelling of 999999801 in words is "nine hundred ninety-nine million, nine hundred ninety-nine thousand, eight hundred one".