2001101209 has 2 divisors, whose sum is σ = 2001101210. Its totient is φ = 2001101208.

The previous prime is 2001101189. The next prime is 2001101257. The reversal of 2001101209 is 9021011002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1514766400 + 486334809 = 38920^2 + 22053^2 .

It is a cyclic number.

It is not a de Polignac number, because 2001101209 - 2²¹ = 1999004057 is a prime.

It is a super-2 number, since 2×2001101209² = 8008812097322523362, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 2001101192 and 2001101201.

It is not a weakly prime, because it can be changed into another prime (2001108209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1000550604 + 1000550605.

It is an arithmetic number, because the mean of its divisors is an integer number (1000550605).

Almost surely, 2^2001101209 is an apocalyptic number.

It is an amenable number.

2001101209 is a deficient number, since it is larger than the sum of its proper divisors (1).

2001101209 is an equidigital number, since it uses as much as digits as its factorization.

2001101209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36, while the sum is 16.

The square root of 2001101209 is about 44733.6697466237. The cubic root of 2001101209 is about 1260.1522468673.

The spelling of 2001101209 in words is "two billion, one million, one hundred one thousand, two hundred nine".