1200021309989 has 2 divisors, whose sum is σ = 1200021309990. Its totient is φ = 1200021309988.

The previous prime is 1200021309919. The next prime is 1200021310001. The reversal of 1200021309989 is 9899031200021.

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., 1156947628225 + 43073681764 = 1075615^2 + 207542^2 .

It is a cyclic number.

It is not a de Polignac number, because 1200021309989 - 2¹⁶ = 1200021244453 is a prime.

It is a super-2 number, since 2×1200021309989² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1200021309919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 600010654994 + 600010654995.

It is an arithmetic number, because the mean of its divisors is an integer number (600010654995).

Almost surely, 2^{1200021309989} is an apocalyptic number.

It is an amenable number.

1200021309989 is a deficient number, since it is larger than the sum of its proper divisors (1).

1200021309989 is an equidigital number, since it uses as much as digits as its factorization.

1200021309989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 69984, while the sum is 44.

The spelling of 1200021309989 in words is "one trillion, two hundred billion, twenty-one million, three hundred nine thousand, nine hundred eighty-nine".