2001320989 has 2 divisors, whose sum is σ = 2001320990. Its totient is φ = 2001320988.

The previous prime is 2001320957. The next prime is 2001321019. The reversal of 2001320989 is 9890231002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1635555364 + 365765625 = 40442^2 + 19125^2 .

It is a cyclic number.

It is not a de Polignac number, because 2001320989 - 2⁵ = 2001320957 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2001320389) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1000660494 + 1000660495.

It is an arithmetic number, because the mean of its divisors is an integer number (1000660495).

Almost surely, 2^2001320989 is an apocalyptic number.

It is an amenable number.

2001320989 is a deficient number, since it is larger than the sum of its proper divisors (1).

2001320989 is an equidigital number, since it uses as much as digits as its factorization.

2001320989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7776, while the sum is 34.

The square root of 2001320989 is about 44736.1262180802. The cubic root of 2001320989 is about 1260.1983791536.

The spelling of 2001320989 in words is "two billion, one million, three hundred twenty thousand, nine hundred eighty-nine".