1001021000009 has 2 divisors, whose sum is σ = 1001021000010. Its totient is φ = 1001021000008.

The previous prime is 1001020999897. The next prime is 1001021000011. The reversal of 1001021000009 is 9000001201001.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 998806356409 + 2214643600 = 999403^2 + 47060^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1001021000009 is a prime.

Together with 1001021000011, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 1001020999957 and 1001021000002.

It is not a weakly prime, because it can be changed into another prime (1001021000039) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 500510500004 + 500510500005.

It is an arithmetic number, because the mean of its divisors is an integer number (500510500005).

Almost surely, 2^{1001021000009} is an apocalyptic number.

It is an amenable number.

1001021000009 is a deficient number, since it is larger than the sum of its proper divisors (1).

1001021000009 is an equidigital number, since it uses as much as digits as its factorization.

1001021000009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18, while the sum is 14.

The spelling of 1001021000009 in words is "one trillion, one billion, twenty-one million, nine", and thus it is an aban number and an uban number.