2001221077 has 2 divisors, whose sum is σ = 2001221078. Its totient is φ = 2001221076.

The previous prime is 2001221071. The next prime is 2001221119. The reversal of 2001221077 is 7701221002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1884775396 + 116445681 = 43414^2 + 10791^2 .

It is a cyclic number.

It is not a de Polignac number, because 2001221077 - 2²⁷ = 1867003349 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2001221071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1000610538 + 1000610539.

It is an arithmetic number, because the mean of its divisors is an integer number (1000610539).

Almost surely, 2^2001221077 is an apocalyptic number.

It is an amenable number.

2001221077 is a deficient number, since it is larger than the sum of its proper divisors (1).

2001221077 is an equidigital number, since it uses as much as digits as its factorization.

2001221077 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 392, while the sum is 22.

The square root of 2001221077 is about 44735.0095227440. The cubic root of 2001221077 is about 1260.1774078325.

Adding to 2001221077 its reverse (7701221002), we get a palindrome (9702442079).

The spelling of 2001221077 in words is "two billion, one million, two hundred twenty-one thousand, seventy-seven".