1002100009 has 4 divisors (see below), whose sum is σ = 1018527940. Its totient is φ = 985672080.

The previous prime is 1002100007. The next prime is 1002100013. The reversal of 1002100009 is 9000012001.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9000012001 = 10333 ⋅870997.

It can be written as a sum of positive squares in 2 ways, for example, as 381342784 + 620757225 = 19528^2 + 24915^2 .

It is a cyclic number.

It is not a de Polignac number, because 1002100009 - 2¹ = 1002100007 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1002100007) 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, 8213874 + ... + 8213995.

It is an arithmetic number, because the mean of its divisors is an integer number (254631985).

Almost surely, 2^1002100009 is an apocalyptic number.

It is an amenable number.

1002100009 is a deficient number, since it is larger than the sum of its proper divisors (16427931).

1002100009 is an equidigital number, since it uses as much as digits as its factorization.

1002100009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16427930.

The product of its (nonzero) digits is 18, while the sum is 13.

The square root of 1002100009 is about 31655.9632454929. The cubic root of 1002100009 is about 1000.6995135667.

The spelling of 1002100009 in words is "one billion, two million, one hundred thousand, nine".