8001001009 has 4 divisors (see below), whose sum is σ = 8006601460. Its totient is φ = 7995400560.

The previous prime is 8001001003. The next prime is 8001001051. The reversal of 8001001009 is 9001001008.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2229256225 + 5771744784 = 47215^2 + 75972^2 .

It is a cyclic number.

It is not a de Polignac number, because 8001001009 - 2¹³ = 8000992817 is a prime.

It is a super-3 number, since 3×8001001009³ (a number of 31 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8001001003) 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, 2798082 + ... + 2800939.

It is an arithmetic number, because the mean of its divisors is an integer number (2001650365).

Almost surely, 2^8001001009 is an apocalyptic number.

It is an amenable number.

8001001009 is a deficient number, since it is larger than the sum of its proper divisors (5600451).

8001001009 is a wasteful number, since it uses less digits than its factorization.

8001001009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5600450.

The product of its (nonzero) digits is 72, while the sum is 19.

The square root of 8001001009 is about 89448.3147353822. The cubic root of 8001001009 is about 2000.0834139377.

Subtracting 8001001009 from its reverse (9001001008), we obtain a palindrome (999999999).

The spelling of 8001001009 in words is "eight billion, one million, one thousand, nine".