801999816 has 64 divisors (see below), whose sum is σ = 2058851520. Its totient is φ = 260232960.

The previous prime is 801999797. The next prime is 801999829. The reversal of 801999816 is 618999108.

It is a happy number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 164226 + ... + 169038.

It is an arithmetic number, because the mean of its divisors is an integer number (32169555).

Almost surely, 2^801999816 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 801999816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1029425760).

801999816 is an abundant number, since it is smaller than the sum of its proper divisors (1256851704).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

801999816 is a wasteful number, since it uses less digits than its factorization.

801999816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5006 (or 5002 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 51.

The square root of 801999816 is about 28319.6012683795. The cubic root of 801999816 is about 929.0906500376.

The spelling of 801999816 in words is "eight hundred one million, nine hundred ninety-nine thousand, eight hundred sixteen".