2001221120077 has 2 divisors, whose sum is σ = 2001221120078. Its totient is φ = 2001221120076.

The previous prime is 2001221120057. The next prime is 2001221120141. The reversal of 2001221120077 is 7700211221002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1861229904361 + 139991215716 = 1364269^2 + 374154^2 .

It is a cyclic number.

It is not a de Polignac number, because 2001221120077 - 2⁷ = 2001221119949 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2001221120057) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1000610560038 + 1000610560039.

It is an arithmetic number, because the mean of its divisors is an integer number (1000610560039).

Almost surely, 2^{2001221120077} is an apocalyptic number.

It is an amenable number.

2001221120077 is a deficient number, since it is larger than the sum of its proper divisors (1).

2001221120077 is an equidigital number, since it uses as much as digits as its factorization.

2001221120077 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 784, while the sum is 25.

Adding to 2001221120077 its reverse (7700211221002), we get a palindrome (9701432341079).

The spelling of 2001221120077 in words is "two trillion, one billion, two hundred twenty-one million, one hundred twenty thousand, seventy-seven".