2001121091 has 2 divisors, whose sum is σ = 2001121092. Its totient is φ = 2001121090.

The previous prime is 2001121037. The next prime is 2001121099. The reversal of 2001121091 is 1901211002.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2001121091 - 2²² = 1996926787 is a prime.

It is not a weakly prime, because it can be changed into another prime (2001121099) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1000560545 + 1000560546.

It is an arithmetic number, because the mean of its divisors is an integer number (1000560546).

Almost surely, 2^2001121091 is an apocalyptic number.

2001121091 is a deficient number, since it is larger than the sum of its proper divisors (1).

2001121091 is an equidigital number, since it uses as much as digits as its factorization.

2001121091 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 17.

The square root of 2001121091 is about 44733.8919724184. The cubic root of 2001121091 is about 1260.1564202800.

Adding to 2001121091 its reverse (1901211002), we get a palindrome (3902332093).

The spelling of 2001121091 in words is "two billion, one million, one hundred twenty-one thousand, ninety-one".