2001121757 has 2 divisors, whose sum is σ = 2001121758. Its totient is φ = 2001121756.

The previous prime is 2001121753. The next prime is 2001121769. The reversal of 2001121757 is 7571211002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1923787321 + 77334436 = 43861^2 + 8794^2 .

It is a cyclic number.

It is not a de Polignac number, because 2001121757 - 2² = 2001121753 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2001121751) 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, 1000560878 + 1000560879.

It is an arithmetic number, because the mean of its divisors is an integer number (1000560879).

Almost surely, 2^2001121757 is an apocalyptic number.

It is an amenable number.

2001121757 is a deficient number, since it is larger than the sum of its proper divisors (1).

2001121757 is an equidigital number, since it uses as much as digits as its factorization.

2001121757 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 980, while the sum is 26.

The square root of 2001121757 is about 44733.8994164381. The cubic root of 2001121757 is about 1260.1565600790.

Adding to 2001121757 its reverse (7571211002), we get a palindrome (9572332759).

The spelling of 2001121757 in words is "two billion, one million, one hundred twenty-one thousand, seven hundred fifty-seven".