781221011201089 has 2 divisors, whose sum is σ = 781221011201090. Its totient is φ = 781221011201088.

The previous prime is 781221011201077. The next prime is 781221011201123. The reversal of 781221011201089 is 980102110122187.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 476129114266689 + 305091896934400 = 21820383^2 + 17466880^2 .

It is a cyclic number.

It is not a de Polignac number, because 781221011201089 - 2⁷ = 781221011200961 is a prime.

It is a super-2 number, since 2×781221011201089² (a number of 31 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (781221011201069) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 390610505600544 + 390610505600545.

It is an arithmetic number, because the mean of its divisors is an integer number (390610505600545).

Almost surely, 2^{781221011201089} is an apocalyptic number.

It is an amenable number.

781221011201089 is a deficient number, since it is larger than the sum of its proper divisors (1).

781221011201089 is an equidigital number, since it uses as much as digits as its factorization.

781221011201089 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32256, while the sum is 43.

The spelling of 781221011201089 in words is "seven hundred eighty-one trillion, two hundred twenty-one billion, eleven million, two hundred one thousand, eighty-nine".