2101001009 has 2 divisors, whose sum is σ = 2101001010. Its totient is φ = 2101001008.

The previous prime is 2101000999. The next prime is 2101001029. The reversal of 2101001009 is 9001001012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2039425600 + 61575409 = 45160^2 + 7847^2 .

It is a cyclic number.

It is not a de Polignac number, because 2101001009 - 2¹² = 2100996913 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2101000984 and 2101001002.

It is not a weakly prime, because it can be changed into another prime (2101001029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1050500504 + 1050500505.

It is an arithmetic number, because the mean of its divisors is an integer number (1050500505).

Almost surely, 2^2101001009 is an apocalyptic number.

It is an amenable number.

2101001009 is a deficient number, since it is larger than the sum of its proper divisors (1).

2101001009 is an equidigital number, since it uses as much as digits as its factorization.

2101001009 is an odious number, because the sum of its binary digits is odd.

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

The square root of 2101001009 is about 45836.6775519343. The cubic root of 2101001009 is about 1280.7826042964.

The spelling of 2101001009 in words is "two billion, one hundred one million, one thousand, nine".