2001205553989 has 2 divisors, whose sum is σ = 2001205553990. Its totient is φ = 2001205553988.

The previous prime is 2001205553933. The next prime is 2001205554031. The reversal of 2001205553989 is 9893555021002.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1897161890625 + 104043663364 = 1377375^2 + 322558^2 .

It is a cyclic number.

It is not a de Polignac number, because 2001205553989 - 2⁷ = 2001205553861 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2001205533989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1000602776994 + 1000602776995.

It is an arithmetic number, because the mean of its divisors is an integer number (1000602776995).

Almost surely, 2^{2001205553989} is an apocalyptic number.

It is an amenable number.

2001205553989 is a deficient number, since it is larger than the sum of its proper divisors (1).

2001205553989 is an equidigital number, since it uses as much as digits as its factorization.

2001205553989 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 972000, while the sum is 49.

The spelling of 2001205553989 in words is "two trillion, one billion, two hundred five million, five hundred fifty-three thousand, nine hundred eighty-nine".